From 5ff6ae89403275bdd684eae7d762b5bb5bf5e85f Mon Sep 17 00:00:00 2001
From: Knacky <knckydev@gmail.com>
Date: Wed, 10 Jun 2026 19:50:11 +0200
Subject: [PATCH] feat(frontend): c2 config card + execute modal (sprint 8
 phase 1)

- frontend/src/api/c2.ts: 6 typed API calls (getC2Config, putC2Config,
  deleteC2Config, testC2Config, listCallbacks, executeC2) following the
  frozen M1+M2 backend contracts
- frontend/src/api/types.ts: C2Config, C2ConfigInput, C2TestResult,
  C2Callback, C2CallbacksResponse, C2Task, C2ExecuteInput, C2ExecuteResponse
- frontend/src/hooks/useC2.ts: useC2Config, useUpdateC2Config,
  useDeleteC2Config, useTestC2Config, useC2Callbacks, useExecuteC2
- frontend/src/components/C2ConfigCard.tsx: engagement-scoped C2 config
  card (url + write-only token + verify-tls + save/delete/test-connection),
  503 disabled state, ConfirmDialog on delete
- frontend/src/components/ExecuteViaC2Modal.tsx: callback picker table
  (mono data cells), commands textarea pre-filled from rt.commands,
  Launch disabled until row selected + non-empty commands
- frontend/src/pages/EngagementFormPage.tsx: embed C2ConfigCard in edit
  mode only, admin+redteam only (canEditEngagements gate)
- frontend/src/pages/SimulationFormPage.tsx: Execute via C2 button in RT
  card, visible only when !isDone && canEditRT && hasC2Config; opens modal
- Tests: 33 new tests across api/c2, components/C2ConfigCard,
  components/ExecuteViaC2Modal, EngagementFormPage, SimulationFormPage
  (172 total, 139 baseline + 33 new, all passing)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 frontend/src/api/c2.ts                        |  60 +++++
 frontend/src/api/types.ts                     |  49 ++++
 frontend/src/components/C2ConfigCard.tsx      | 240 ++++++++++++++++++
 frontend/src/components/ExecuteViaC2Modal.tsx | 186 ++++++++++++++
 frontend/src/hooks/useC2.ts                   |  81 ++++++
 frontend/src/pages/EngagementFormPage.tsx     |   7 +
 frontend/src/pages/SimulationFormPage.tsx     |  33 ++-
 frontend/tests/EngagementFormPage.test.tsx    | 108 ++++++++
 frontend/tests/SimulationFormPage.test.tsx    |  59 +++++
 frontend/tests/api/c2.test.ts                 | 136 ++++++++++
 .../tests/components/C2ConfigCard.test.tsx    | 135 ++++++++++
 .../components/ExecuteViaC2Modal.test.tsx     | 160 ++++++++++++
 12 files changed, 1253 insertions(+), 1 deletion(-)
 create mode 100644 frontend/src/api/c2.ts
 create mode 100644 frontend/src/components/C2ConfigCard.tsx
 create mode 100644 frontend/src/components/ExecuteViaC2Modal.tsx
 create mode 100644 frontend/src/hooks/useC2.ts
 create mode 100644 frontend/tests/EngagementFormPage.test.tsx
 create mode 100644 frontend/tests/api/c2.test.ts
 create mode 100644 frontend/tests/components/C2ConfigCard.test.tsx
 create mode 100644 frontend/tests/components/ExecuteViaC2Modal.test.tsx

diff --git a/frontend/src/api/c2.ts b/frontend/src/api/c2.ts
new file mode 100644
index 0000000..d4fe677
--- /dev/null
+++ b/frontend/src/api/c2.ts
@@ -0,0 +1,60 @@
+import { apiClient } from './client';
+import type {
+  C2Config,
+  C2ConfigInput,
+  C2TestResult,
+  C2CallbacksResponse,
+  C2ExecuteInput,
+  C2ExecuteResponse,
+} from './types';
+
+export async function getC2Config(engagementId: number): Promise<C2Config | null> {
+  try {
+    const { data } = await apiClient.get<C2Config>(`/engagements/${engagementId}/c2-config`);
+    return data;
+  } catch (err: unknown) {
+    const e = err as { response?: { status?: number } };
+    if (e?.response?.status === 404) return null;
+    throw err;
+  }
+}
+
+export async function putC2Config(
+  engagementId: number,
+  input: C2ConfigInput,
+): Promise<C2Config> {
+  const { data } = await apiClient.put<C2Config>(
+    `/engagements/${engagementId}/c2-config`,
+    input,
+  );
+  return data;
+}
+
+export async function deleteC2Config(engagementId: number): Promise<void> {
+  await apiClient.delete(`/engagements/${engagementId}/c2-config`);
+}
+
+export async function testC2Config(engagementId: number): Promise<C2TestResult> {
+  const { data } = await apiClient.post<C2TestResult>(
+    `/engagements/${engagementId}/c2-config/test`,
+  );
+  return data;
+}
+
+export async function listCallbacks(engagementId: number): Promise<C2CallbacksResponse> {
+  const { data } = await apiClient.get<C2CallbacksResponse>(
+    `/engagements/${engagementId}/c2/callbacks`,
+  );
+  return data;
+}
+
+export async function executeC2(
+  simulationId: number,
+  input: C2ExecuteInput,
+): Promise<C2ExecuteResponse> {
+  const { data } = await apiClient.post<C2ExecuteResponse>(
+    `/simulations/${simulationId}/c2/execute`,
+    input,
+  );
+  return data;
+}
diff --git a/frontend/src/api/types.ts b/frontend/src/api/types.ts
index 3c977eb..b51f45b 100644
--- a/frontend/src/api/types.ts
+++ b/frontend/src/api/types.ts
@@ -154,3 +154,52 @@ export interface SimulationPatchInput {
   soc_comment?: string | null;
   incident_number?: string | null;
 }
+
+// C2 types
+
+export interface C2Config {
+  has_token: boolean;
+  url: string;
+  verify_tls: boolean;
+}
+
+export interface C2ConfigInput {
+  url: string;
+  api_token?: string;
+  verify_tls: boolean;
+}
+
+export interface C2TestResult {
+  ok: boolean;
+  error: string | null;
+}
+
+export interface C2Callback {
+  display_id: number;
+  active: boolean;
+  host: string;
+  user: string;
+  domain: string;
+  last_checkin: string;
+}
+
+export interface C2CallbacksResponse {
+  callbacks: C2Callback[];
+}
+
+export interface C2Task {
+  id: number;
+  mythic_task_display_id: number;
+  command: string;
+  status: string;
+  completed: boolean;
+}
+
+export interface C2ExecuteInput {
+  callback_display_id: number;
+  commands: string[];
+}
+
+export interface C2ExecuteResponse {
+  tasks: C2Task[];
+}
diff --git a/frontend/src/components/C2ConfigCard.tsx b/frontend/src/components/C2ConfigCard.tsx
new file mode 100644
index 0000000..1363310
--- /dev/null
+++ b/frontend/src/components/C2ConfigCard.tsx
@@ -0,0 +1,240 @@
+import { useEffect, useState, type FormEvent } from 'react';
+import { extractApiError } from '@/api/client';
+import { useC2Config, useDeleteC2Config, useTestC2Config, useUpdateC2Config } from '@/hooks/useC2';
+import { ConfirmDialog } from './ConfirmDialog';
+import { FormField, TextInput } from './FormField';
+import { useToast } from '@/hooks/useToast';
+
+interface C2ConfigCardProps {
+  engagementId: number;
+}
+
+export function C2ConfigCard({ engagementId }: C2ConfigCardProps): JSX.Element {
+  const { push } = useToast();
+
+  const configQuery = useC2Config(engagementId);
+  const updateMutation = useUpdateC2Config(engagementId);
+  const deleteMutation = useDeleteC2Config(engagementId);
+  const testMutation = useTestC2Config(engagementId);
+
+  const config = configQuery.data;
+  const is503 = configQuery.error
+    ? (configQuery.error as { response?: { status?: number } })?.response?.status === 503
+    : false;
+
+  const [url, setUrl] = useState('');
+  const [token, setToken] = useState('');
+  const [verifyTls, setVerifyTls] = useState(true);
+  const [replaceToken, setReplaceToken] = useState(false);
+  const [showDeleteConfirm, setShowDeleteConfirm] = useState(false);
+  const [testResult, setTestResult] = useState<{ ok: boolean; message: string } | null>(null);
+
+  // Sync URL and verifyTls from loaded config (but not token — write-only at API level)
+  useEffect(() => {
+    if (config) {
+      setUrl(config.url);
+      setVerifyTls(config.verify_tls);
+    }
+  }, [config]);
+
+  const disabled = is503 || configQuery.isLoading;
+
+  const onSave = async (e: FormEvent) => {
+    e.preventDefault();
+    if (is503) return;
+    setTestResult(null);
+
+    const input: { url: string; verify_tls: boolean; api_token?: string } = {
+      url: url.trim(),
+      verify_tls: verifyTls,
+    };
+    // Send token only if: no existing config, OR user explicitly chose to replace
+    if (!config?.has_token || replaceToken) {
+      if (token.trim()) input.api_token = token.trim();
+    }
+
+    try {
+      await updateMutation.mutateAsync(input);
+      push('C2 configuration saved', 'success');
+      setToken('');
+      setReplaceToken(false);
+    } catch (err) {
+      push(extractApiError(err, 'Could not save C2 configuration'), 'error');
+    }
+  };
+
+  const onDelete = async () => {
+    setShowDeleteConfirm(false);
+    setTestResult(null);
+    try {
+      await deleteMutation.mutateAsync();
+      push('C2 configuration removed', 'success');
+      setUrl('');
+      setToken('');
+      setVerifyTls(true);
+      setReplaceToken(false);
+    } catch (err) {
+      push(extractApiError(err, 'Could not remove C2 configuration'), 'error');
+    }
+  };
+
+  const onTest = async () => {
+    setTestResult(null);
+    try {
+      const result = await testMutation.mutateAsync();
+      setTestResult({
+        ok: result.ok,
+        message: result.ok ? 'Connected' : (result.error ?? 'Connection failed'),
+      });
+    } catch (err) {
+      setTestResult({ ok: false, message: extractApiError(err, 'Test failed') });
+    }
+  };
+
+  const submitting = updateMutation.isPending || deleteMutation.isPending;
+
+  return (
+    <div
+      data-testid="c2-config-card"
+      className="card-product flex flex-col gap-md"
+    >
+      <h2 className="text-[20px] font-medium text-ink">C2 configuration</h2>
+
+      {is503 && (
+        <div
+          role="alert"
+          className="rounded-none px-xl py-md bg-fog border border-hairline text-[14px] text-charcoal"
+        >
+          C2 features are disabled (server has no encryption key configured).
+        </div>
+      )}
+
+      {configQuery.isLoading ? (
+        <p className="text-[14px] text-graphite">Loading…</p>
+      ) : (
+        <form onSubmit={onSave} noValidate className="flex flex-col gap-md">
+          <FormField
+            label="URL"
+            htmlFor="c2-url"
+            hint="HTTPS required (e.g. https://mythic.lab:7443)"
+          >
+            <TextInput
+              id="c2-url"
+              data-testid="c2-url-input"
+              type="url"
+              name="url"
+              placeholder="https://mythic.lab:7443"
+              value={url}
+              onChange={(e) => setUrl(e.target.value)}
+              disabled={disabled}
+            />
+          </FormField>
+
+          <FormField label="API token" htmlFor="c2-token">
+            {config?.has_token && !replaceToken ? (
+              <div className="flex items-center gap-md">
+                <TextInput
+                  id="c2-token"
+                  data-testid="c2-token-input"
+                  type="password"
+                  name="api_token"
+                  placeholder="••••••••"
+                  value=""
+                  readOnly
+                  disabled={disabled}
+                />
+                <button
+                  type="button"
+                  className="btn-text-link text-[14px] whitespace-nowrap"
+                  onClick={() => setReplaceToken(true)}
+                  disabled={disabled}
+                >
+                  Replace token
+                </button>
+              </div>
+            ) : (
+              <TextInput
+                id="c2-token"
+                data-testid="c2-token-input"
+                type="password"
+                name="api_token"
+                placeholder={config?.has_token ? 'Enter new token' : 'API token'}
+                value={token}
+                onChange={(e) => setToken(e.target.value)}
+                disabled={disabled}
+              />
+            )}
+          </FormField>
+
+          <div className="flex items-center gap-sm">
+            <input
+              id="c2-verify-tls"
+              data-testid="c2-verify-tls"
+              type="checkbox"
+              checked={verifyTls}
+              onChange={(e) => setVerifyTls(e.target.checked)}
+              disabled={disabled}
+              className="h-4 w-4 accent-primary"
+            />
+            <label htmlFor="c2-verify-tls" className="text-[14px] text-ink">
+              Verify TLS certificate
+            </label>
+          </div>
+
+          <div className="flex items-center gap-md flex-wrap">
+            <button
+              type="submit"
+              data-testid="c2-save-btn"
+              className="btn-primary"
+              disabled={disabled || submitting}
+            >
+              {updateMutation.isPending ? 'Saving…' : 'Save'}
+            </button>
+
+            <button
+              type="button"
+              data-testid="c2-test-btn"
+              className="btn-outline"
+              onClick={onTest}
+              disabled={disabled || testMutation.isPending || !config}
+            >
+              {testMutation.isPending ? 'Testing…' : 'Test connection'}
+            </button>
+
+            {testResult !== null && (
+              <span
+                className={`text-[14px] ${testResult.ok ? 'text-success' : 'text-bloom-deep'}`}
+              >
+                {testResult.message}
+              </span>
+            )}
+
+            {config?.has_token && (
+              <button
+                type="button"
+                data-testid="c2-delete-btn"
+                className="btn-text-link text-bloom-deep ml-auto"
+                onClick={() => setShowDeleteConfirm(true)}
+                disabled={disabled || submitting}
+              >
+                Delete configuration
+              </button>
+            )}
+          </div>
+        </form>
+      )}
+
+      {showDeleteConfirm && (
+        <ConfirmDialog
+          title="Delete C2 configuration"
+          description="This will remove the C2 configuration for this engagement. The API token will be permanently deleted."
+          confirmLabel="Delete"
+          cancelLabel="Cancel"
+          destructive
+          onConfirm={onDelete}
+          onCancel={() => setShowDeleteConfirm(false)}
+        />
+      )}
+    </div>
+  );
+}
diff --git a/frontend/src/components/ExecuteViaC2Modal.tsx b/frontend/src/components/ExecuteViaC2Modal.tsx
new file mode 100644
index 0000000..2d621a0
--- /dev/null
+++ b/frontend/src/components/ExecuteViaC2Modal.tsx
@@ -0,0 +1,186 @@
+import { useState } from 'react';
+import { extractApiError } from '@/api/client';
+import { useC2Callbacks, useExecuteC2 } from '@/hooks/useC2';
+import type { C2Callback } from '@/api/types';
+import { useToast } from '@/hooks/useToast';
+
+interface ExecuteViaC2ModalProps {
+  simulationId: number;
+  engagementId: number;
+  initialCommands: string;
+  onClose: () => void;
+}
+
+function formatCheckin(ts: string): string {
+  // Show ISO timestamp as-is — it's a data cell (font-mono)
+  return ts;
+}
+
+export function ExecuteViaC2Modal({
+  simulationId,
+  engagementId,
+  initialCommands,
+  onClose,
+}: ExecuteViaC2ModalProps): JSX.Element {
+  const { push } = useToast();
+
+  const callbacksQuery = useC2Callbacks(engagementId, { enabled: true });
+  const executeMutation = useExecuteC2(simulationId, engagementId);
+
+  const [selectedId, setSelectedId] = useState<number | null>(null);
+  const [commands, setCommands] = useState(initialCommands);
+  const [submitError, setSubmitError] = useState<string | null>(null);
+
+  const callbacks: C2Callback[] = callbacksQuery.data?.callbacks ?? [];
+
+  const commandLines = commands
+    .split('\n')
+    .map((l) => l.trim())
+    .filter(Boolean);
+
+  const canLaunch = selectedId !== null && commandLines.length > 0;
+
+  const onLaunch = async () => {
+    if (!canLaunch) return;
+    setSubmitError(null);
+    try {
+      const result = await executeMutation.mutateAsync({
+        callback_display_id: selectedId,
+        commands: commandLines,
+      });
+      push(`${result.tasks.length} task(s) submitted`, 'success');
+      onClose();
+    } catch (err) {
+      setSubmitError(extractApiError(err, 'Could not execute via C2'));
+    }
+  };
+
+  return (
+    <div
+      role="dialog"
+      aria-modal="true"
+      aria-labelledby="c2-modal-title"
+      data-testid="c2-modal"
+      className="fixed inset-0 z-50 flex items-center justify-center"
+    >
+      <div className="modal-backdrop absolute inset-0" onClick={onClose} aria-hidden="true" />
+
+      <div className="relative card-product w-full max-w-3xl mx-md flex flex-col gap-md max-h-[90vh] overflow-y-auto">
+        <h2 id="c2-modal-title" className="text-[20px] font-medium text-ink">
+          Execute via C2
+        </h2>
+
+        {/* Callback table */}
+        <div className="flex flex-col gap-xs">
+          <span className="text-[14px] font-medium text-ink">Select callback</span>
+
+          {callbacksQuery.isLoading && (
+            <p className="text-[14px] text-graphite">Loading callbacks…</p>
+          )}
+
+          {callbacksQuery.isError && (
+            <p className="text-[14px] text-bloom-deep">
+              Could not load callbacks: {extractApiError(callbacksQuery.error, 'Unknown error')}
+            </p>
+          )}
+
+          {!callbacksQuery.isLoading && callbacks.length === 0 && !callbacksQuery.isError && (
+            <p className="text-[14px] text-graphite">No callbacks available.</p>
+          )}
+
+          {callbacks.length > 0 && (
+            <div className="border border-hairline overflow-x-auto">
+              <table className="w-full text-[14px]">
+                <thead>
+                  <tr className="bg-cloud border-b border-hairline">
+                    <th className="px-md py-sm text-left font-medium text-ink">Display ID</th>
+                    <th className="px-md py-sm text-left font-medium text-ink">Active</th>
+                    <th className="px-md py-sm text-left font-medium text-ink">Host</th>
+                    <th className="px-md py-sm text-left font-medium text-ink">User</th>
+                    <th className="px-md py-sm text-left font-medium text-ink">Domain</th>
+                    <th className="px-md py-sm text-left font-medium text-ink">Last check-in</th>
+                  </tr>
+                </thead>
+                <tbody>
+                  {callbacks.map((cb) => {
+                    const isSelected = selectedId === cb.display_id;
+                    return (
+                      <tr
+                        key={cb.display_id}
+                        data-testid="c2-callback-row"
+                        onClick={() => setSelectedId(cb.display_id)}
+                        className={`cursor-pointer border-b border-hairline ${
+                          isSelected
+                            ? 'bg-primary-soft'
+                            : 'hover:bg-cloud'
+                        }`}
+                      >
+                        <td className="px-md py-sm font-mono">{cb.display_id}</td>
+                        <td className="px-md py-sm">
+                          <span
+                            className={`badge-pill-${cb.active ? 'active' : 'inactive'}`}
+                          >
+                            {cb.active ? 'Active' : 'Inactive'}
+                          </span>
+                        </td>
+                        <td className="px-md py-sm font-mono">{cb.host}</td>
+                        <td className="px-md py-sm font-mono">{cb.user}</td>
+                        <td className="px-md py-sm font-mono">{cb.domain}</td>
+                        <td className="px-md py-sm font-mono">{formatCheckin(cb.last_checkin)}</td>
+                      </tr>
+                    );
+                  })}
+                </tbody>
+              </table>
+            </div>
+          )}
+        </div>
+
+        {/* Commands */}
+        <div className="flex flex-col gap-xs">
+          <label htmlFor="c2-commands" className="text-[14px] font-medium text-ink">
+            Commands
+          </label>
+          <textarea
+            id="c2-commands"
+            data-testid="c2-commands-textarea"
+            value={commands}
+            onChange={(e) => setCommands(e.target.value)}
+            className="text-input min-h-[112px] py-sm font-mono text-[14px]"
+            placeholder="One command per line"
+          />
+          <span className="text-[12px] text-graphite">
+            {commandLines.length} command{commandLines.length !== 1 ? 's' : ''} — one task per line
+          </span>
+        </div>
+
+        {submitError && (
+          <p role="alert" className="text-[14px] text-bloom-deep">
+            {submitError}
+          </p>
+        )}
+
+        {/* Footer */}
+        <div className="flex items-center gap-md pt-xs">
+          <button
+            type="button"
+            data-testid="c2-launch-btn"
+            className="btn-primary"
+            onClick={onLaunch}
+            disabled={!canLaunch || executeMutation.isPending}
+          >
+            {executeMutation.isPending ? 'Launching…' : 'Launch'}
+          </button>
+          <button
+            type="button"
+            className="btn-outline-ink"
+            onClick={onClose}
+            disabled={executeMutation.isPending}
+          >
+            Cancel
+          </button>
+        </div>
+      </div>
+    </div>
+  );
+}
diff --git a/frontend/src/hooks/useC2.ts b/frontend/src/hooks/useC2.ts
new file mode 100644
index 0000000..343db3f
--- /dev/null
+++ b/frontend/src/hooks/useC2.ts
@@ -0,0 +1,81 @@
+import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
+import {
+  deleteC2Config,
+  executeC2,
+  getC2Config,
+  listCallbacks,
+  putC2Config,
+  testC2Config,
+} from '@/api/c2';
+import type { C2ConfigInput, C2ExecuteInput } from '@/api/types';
+
+function c2ConfigKey(engagementId: number) {
+  return ['c2-config', engagementId] as const;
+}
+
+function c2CallbacksKey(engagementId: number) {
+  return ['c2-callbacks', engagementId] as const;
+}
+
+function simulationKey(id: number) {
+  return ['simulations', id] as const;
+}
+
+export function useC2Config(engagementId: number | undefined, options?: { enabled?: boolean }) {
+  const enabled =
+    typeof engagementId === 'number' &&
+    !Number.isNaN(engagementId) &&
+    (options?.enabled !== false);
+
+  return useQuery({
+    queryKey: engagementId ? c2ConfigKey(engagementId) : ['c2-config', 'none'],
+    queryFn: () => getC2Config(engagementId as number),
+    enabled,
+  });
+}
+
+export function useUpdateC2Config(engagementId: number) {
+  const qc = useQueryClient();
+  return useMutation({
+    mutationFn: (input: C2ConfigInput) => putC2Config(engagementId, input),
+    onSuccess: () => qc.invalidateQueries({ queryKey: c2ConfigKey(engagementId) }),
+  });
+}
+
+export function useDeleteC2Config(engagementId: number) {
+  const qc = useQueryClient();
+  return useMutation({
+    mutationFn: () => deleteC2Config(engagementId),
+    onSuccess: () => qc.invalidateQueries({ queryKey: c2ConfigKey(engagementId) }),
+  });
+}
+
+export function useTestC2Config(engagementId: number) {
+  return useMutation({
+    mutationFn: () => testC2Config(engagementId),
+  });
+}
+
+export function useC2Callbacks(engagementId: number | undefined, options?: { enabled?: boolean }) {
+  const enabled =
+    typeof engagementId === 'number' &&
+    !Number.isNaN(engagementId) &&
+    (options?.enabled !== false);
+
+  return useQuery({
+    queryKey: engagementId ? c2CallbacksKey(engagementId) : ['c2-callbacks', 'none'],
+    queryFn: () => listCallbacks(engagementId as number),
+    enabled,
+  });
+}
+
+export function useExecuteC2(simulationId: number, engagementId: number) {
+  const qc = useQueryClient();
+  return useMutation({
+    mutationFn: (input: C2ExecuteInput) => executeC2(simulationId, input),
+    onSuccess: () => {
+      qc.invalidateQueries({ queryKey: simulationKey(simulationId) });
+      qc.invalidateQueries({ queryKey: ['engagements', engagementId, 'simulations'] });
+    },
+  });
+}
diff --git a/frontend/src/pages/EngagementFormPage.tsx b/frontend/src/pages/EngagementFormPage.tsx
index 5495772..6fa635c 100644
--- a/frontend/src/pages/EngagementFormPage.tsx
+++ b/frontend/src/pages/EngagementFormPage.tsx
@@ -7,10 +7,12 @@ import {
   useEngagement,
   usePatchEngagement,
 } from '@/hooks/useEngagements';
+import { useAuth } from '@/hooks/useAuth';
 import { useToast } from '@/hooks/useToast';
 import { FormField, Select, TextArea, TextInput } from '@/components/FormField';
 import { LoadingState } from '@/components/LoadingState';
 import { ErrorState } from '@/components/ErrorState';
+import { C2ConfigCard } from '@/components/C2ConfigCard';
 
 const STATUS_OPTIONS: { value: EngagementStatus; label: string }[] = [
   { value: 'planned', label: 'Planned' },
@@ -50,6 +52,7 @@ export function EngagementFormPage(): JSX.Element {
   const numericId = id ? Number(id) : undefined;
   const navigate = useNavigate();
   const { push } = useToast();
+  const { canEditEngagements } = useAuth();
 
   const detail = useEngagement(editing ? numericId : undefined);
   const createMutation = useCreateEngagement();
@@ -214,6 +217,10 @@ export function EngagementFormPage(): JSX.Element {
           </Link>
         </div>
       </form>
+
+      {editing && numericId && canEditEngagements && (
+        <C2ConfigCard engagementId={numericId} />
+      )}
     </div>
   );
 }
diff --git a/frontend/src/pages/SimulationFormPage.tsx b/frontend/src/pages/SimulationFormPage.tsx
index 2d97649..3fa75e8 100644
--- a/frontend/src/pages/SimulationFormPage.tsx
+++ b/frontend/src/pages/SimulationFormPage.tsx
@@ -12,12 +12,14 @@ import {
   useTransitionSimulation,
   useUpdateSimulation,
 } from '@/hooks/useSimulations';
+import { useC2Config } from '@/hooks/useC2';
 import { FormField, TextArea, TextInput } from '@/components/FormField';
 import { LoadingState } from '@/components/LoadingState';
 import { ErrorState } from '@/components/ErrorState';
 import { SimulationStatusBadge } from '@/components/SimulationStatusBadge';
 import { ConfirmDialog } from '@/components/ConfirmDialog';
 import { MitreTechniquesField } from '@/components/MitreTechniquesField';
+import { ExecuteViaC2Modal } from '@/components/ExecuteViaC2Modal';
 
 interface RedteamFormState {
   name: string;
@@ -61,6 +63,13 @@ export function SimulationFormPage(): JSX.Element {
   const { push } = useToast();
   const { isAdmin, isRedteam, isSoc, canEditEngagements } = useAuth();
 
+  const canEditRT = isAdmin || isRedteam;
+  const c2ConfigQuery = useC2Config(
+    !isNew && typeof engagementId === 'number' ? engagementId : undefined,
+    { enabled: !isNew && canEditRT },
+  );
+  const hasC2Config = c2ConfigQuery.data !== null && c2ConfigQuery.data !== undefined;
+
   const detail = useSimulation(isNew ? undefined : simulationId);
   const createMutation = useCreateSimulation(engagementId ?? 0);
   const updateMutation = useUpdateSimulation(simulationId ?? 0, engagementId ?? 0);
@@ -72,6 +81,7 @@ export function SimulationFormPage(): JSX.Element {
   const [nameError, setNameError] = useState<string | null>(null);
   const [submitError, setSubmitError] = useState<string | null>(null);
   const [showDeleteConfirm, setShowDeleteConfirm] = useState(false);
+  const [showC2Modal, setShowC2Modal] = useState(false);
 
   useEffect(() => {
     if (!isNew && detail.data) {
@@ -109,7 +119,6 @@ export function SimulationFormPage(): JSX.Element {
   // US-18: Done = fully read-only, Reopen only
   const isDone = status === 'done';
 
-  const canEditRT = isAdmin || isRedteam;
   const socCanEdit = isSoc && (status === 'review_required' || status === 'done');
   const socBlocked = isSoc && (status === 'pending' || status === 'in_progress');
 
@@ -383,6 +392,19 @@ export function SimulationFormPage(): JSX.Element {
               rows={5}
             />
           </FormField>
+
+          {!isDone && canEditRT && hasC2Config && (
+            <div className="pt-xs">
+              <button
+                type="button"
+                data-testid="c2-execute-btn"
+                className="btn-outline"
+                onClick={() => setShowC2Modal(true)}
+              >
+                Execute via C2
+              </button>
+            </div>
+          )}
         </form>
 
         {/* SOC card */}
@@ -512,6 +534,15 @@ export function SimulationFormPage(): JSX.Element {
           onCancel={() => setShowDeleteConfirm(false)}
         />
       )}
+
+      {showC2Modal && simulationId && typeof engagementId === 'number' && (
+        <ExecuteViaC2Modal
+          simulationId={simulationId}
+          engagementId={engagementId}
+          initialCommands={rt.commands}
+          onClose={() => setShowC2Modal(false)}
+        />
+      )}
     </div>
   );
 }
diff --git a/frontend/tests/EngagementFormPage.test.tsx b/frontend/tests/EngagementFormPage.test.tsx
new file mode 100644
index 0000000..0de3ee5
--- /dev/null
+++ b/frontend/tests/EngagementFormPage.test.tsx
@@ -0,0 +1,108 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+import { screen, waitFor } from '@testing-library/react';
+import { Route, Routes } from 'react-router-dom';
+import MockAdapter from 'axios-mock-adapter';
+import { apiClient } from '@/api/client';
+import { EngagementFormPage } from '@/pages/EngagementFormPage';
+import { renderWithProviders } from './utils';
+import type { Engagement } from '@/api/types';
+
+const ENGAGEMENT: Engagement = {
+  id: 5,
+  name: 'Test Engagement',
+  description: null,
+  start_date: '2026-06-01',
+  end_date: null,
+  status: 'active',
+  created_at: '2026-06-01T08:00:00',
+  created_by: { id: 1, username: 'alice' },
+};
+
+type MockRole = 'admin' | 'redteam' | 'soc';
+let mockRole: MockRole = 'admin';
+
+vi.mock('@/hooks/useAuth', () => ({
+  useAuth: () => ({
+    user: { id: 1, username: 'alice', role: mockRole, created_at: '2026-01-01' },
+    status: 'authenticated',
+    login: vi.fn(),
+    logout: vi.fn(),
+    isAdmin: mockRole === 'admin',
+    isRedteam: mockRole === 'redteam',
+    isSoc: mockRole === 'soc',
+    canEditEngagements: mockRole === 'admin' || mockRole === 'redteam',
+  }),
+}));
+
+function EditPage() {
+  return (
+    <Routes>
+      <Route path="/engagements/:id/edit" element={<EngagementFormPage />} />
+    </Routes>
+  );
+}
+
+function NewPage() {
+  return (
+    <Routes>
+      <Route path="/engagements/new" element={<EngagementFormPage />} />
+    </Routes>
+  );
+}
+
+describe('EngagementFormPage — C2 config card visibility', () => {
+  let mock: MockAdapter;
+
+  beforeEach(() => {
+    mock = new MockAdapter(apiClient);
+    mock.onGet('/engagements/5').reply(200, ENGAGEMENT);
+    mock.onGet('/engagements/5/c2-config').reply(404);
+  });
+
+  afterEach(() => {
+    mock.restore();
+    vi.clearAllMocks();
+  });
+
+  it('shows C2 config card in EDIT mode for admin', async () => {
+    mockRole = 'admin';
+    renderWithProviders(<EditPage />, {
+      routerProps: { initialEntries: ['/engagements/5/edit'] },
+    });
+    await waitFor(() => {
+      expect(screen.getByTestId('c2-config-card')).toBeInTheDocument();
+    });
+  });
+
+  it('shows C2 config card in EDIT mode for redteam', async () => {
+    mockRole = 'redteam';
+    renderWithProviders(<EditPage />, {
+      routerProps: { initialEntries: ['/engagements/5/edit'] },
+    });
+    await waitFor(() => {
+      expect(screen.getByTestId('c2-config-card')).toBeInTheDocument();
+    });
+  });
+
+  it('does NOT show C2 config card in EDIT mode for SOC', async () => {
+    mockRole = 'soc';
+    renderWithProviders(<EditPage />, {
+      routerProps: { initialEntries: ['/engagements/5/edit'] },
+    });
+    await waitFor(() => {
+      expect(screen.getByRole('button', { name: /save changes/i })).toBeInTheDocument();
+    });
+    expect(screen.queryByTestId('c2-config-card')).toBeNull();
+  });
+
+  it('does NOT show C2 config card on the NEW engagement form', async () => {
+    mockRole = 'admin';
+    renderWithProviders(<NewPage />, {
+      routerProps: { initialEntries: ['/engagements/new'] },
+    });
+    await waitFor(() => {
+      expect(screen.getByRole('button', { name: /create engagement/i })).toBeInTheDocument();
+    });
+    expect(screen.queryByTestId('c2-config-card')).toBeNull();
+  });
+});
diff --git a/frontend/tests/SimulationFormPage.test.tsx b/frontend/tests/SimulationFormPage.test.tsx
index b43bf1a..cba548a 100644
--- a/frontend/tests/SimulationFormPage.test.tsx
+++ b/frontend/tests/SimulationFormPage.test.tsx
@@ -67,6 +67,7 @@ describe('SimulationFormPage — redteam mode (edit existing)', () => {
     mockRole = 'redteam';
     mock = new MockAdapter(apiClient);
     mock.onGet('/simulations/7').reply(200, BASE_SIM);
+    mock.onGet('/engagements/42/c2-config').reply(404);
   });
 
   afterEach(() => {
@@ -154,6 +155,8 @@ describe('SimulationFormPage — SOC role + pending (blocked)', () => {
     mockRole = 'soc';
     mock = new MockAdapter(apiClient);
     mock.onGet('/simulations/7').reply(200, BASE_SIM);
+    // SOC role: useC2Config disabled (canEditRT=false), so no request expected — stub anyway
+    mock.onGet('/engagements/42/c2-config').reply(404);
   });
 
   afterEach(() => {
@@ -202,6 +205,7 @@ describe('SimulationFormPage — SOC role + review_required (can edit SOC fields
     mockRole = 'soc';
     mock = new MockAdapter(apiClient);
     mock.onGet('/simulations/7').reply(200, { ...BASE_SIM, status: 'review_required' });
+    mock.onGet('/engagements/42/c2-config').reply(404);
   });
 
   afterEach(() => {
@@ -273,3 +277,58 @@ describe('SimulationFormPage — new simulation', () => {
     expect(screen.getByRole('button', { name: /Create simulation/i })).toBeInTheDocument();
   });
 });
+
+describe('SimulationFormPage — Execute via C2 button visibility', () => {
+  let mock: MockAdapter;
+
+  beforeEach(() => {
+    mockRole = 'redteam';
+    mock = new MockAdapter(apiClient);
+    mock.onGet('/simulations/7').reply(200, BASE_SIM);
+  });
+
+  afterEach(() => {
+    mock.restore();
+  });
+
+  it('shows Execute via C2 button when c2 config exists', async () => {
+    mock.onGet('/engagements/42/c2-config').reply(200, {
+      has_token: true,
+      url: 'https://mythic.lab:7443',
+      verify_tls: true,
+    });
+    renderWithProviders(<EditPage />, {
+      routerProps: { initialEntries: ['/engagements/42/simulations/7/edit'] },
+    });
+    await waitFor(() => {
+      expect(screen.getByTestId('c2-execute-btn')).toBeInTheDocument();
+    });
+  });
+
+  it('hides Execute via C2 button when no c2 config (404)', async () => {
+    mock.onGet('/engagements/42/c2-config').reply(404);
+    renderWithProviders(<EditPage />, {
+      routerProps: { initialEntries: ['/engagements/42/simulations/7/edit'] },
+    });
+    await waitFor(() => {
+      expect(screen.getByLabelText(/^Name/i)).not.toBeDisabled();
+    });
+    expect(screen.queryByTestId('c2-execute-btn')).toBeNull();
+  });
+
+  it('hides Execute via C2 button when simulation is done', async () => {
+    mock.onGet('/simulations/7').reply(200, { ...BASE_SIM, status: 'done' });
+    mock.onGet('/engagements/42/c2-config').reply(200, {
+      has_token: true,
+      url: 'https://mythic.lab:7443',
+      verify_tls: true,
+    });
+    renderWithProviders(<EditPage />, {
+      routerProps: { initialEntries: ['/engagements/42/simulations/7/edit'] },
+    });
+    await waitFor(() => {
+      expect(screen.getByTestId('reopen-btn')).toBeInTheDocument();
+    });
+    expect(screen.queryByTestId('c2-execute-btn')).toBeNull();
+  });
+});
diff --git a/frontend/tests/api/c2.test.ts b/frontend/tests/api/c2.test.ts
new file mode 100644
index 0000000..e9d9c9d
--- /dev/null
+++ b/frontend/tests/api/c2.test.ts
@@ -0,0 +1,136 @@
+import { afterEach, beforeEach, describe, expect, it } from 'vitest';
+import MockAdapter from 'axios-mock-adapter';
+import { apiClient } from '@/api/client';
+import {
+  deleteC2Config,
+  executeC2,
+  getC2Config,
+  listCallbacks,
+  putC2Config,
+  testC2Config,
+} from '@/api/c2';
+
+let mock: MockAdapter;
+
+beforeEach(() => {
+  mock = new MockAdapter(apiClient);
+});
+
+afterEach(() => {
+  mock.restore();
+});
+
+describe('getC2Config', () => {
+  it('returns config on 200', async () => {
+    mock.onGet('/engagements/1/c2-config').reply(200, {
+      has_token: true,
+      url: 'https://mythic.lab:7443',
+      verify_tls: true,
+    });
+    const result = await getC2Config(1);
+    expect(result).toEqual({ has_token: true, url: 'https://mythic.lab:7443', verify_tls: true });
+  });
+
+  it('returns null on 404', async () => {
+    mock.onGet('/engagements/1/c2-config').reply(404);
+    const result = await getC2Config(1);
+    expect(result).toBeNull();
+  });
+
+  it('throws on other errors', async () => {
+    mock.onGet('/engagements/1/c2-config').reply(503);
+    await expect(getC2Config(1)).rejects.toThrow();
+  });
+});
+
+describe('putC2Config', () => {
+  it('sends PUT to correct URL with body', async () => {
+    mock.onPut('/engagements/2/c2-config').reply(200, {
+      has_token: true,
+      url: 'https://mythic.lab:7443',
+      verify_tls: false,
+    });
+    const result = await putC2Config(2, {
+      url: 'https://mythic.lab:7443',
+      api_token: 'secret',
+      verify_tls: false,
+    });
+    expect(result.has_token).toBe(true);
+    expect(result.verify_tls).toBe(false);
+    const req = mock.history['put'][0];
+    expect(req.url).toBe('/engagements/2/c2-config');
+    const body = JSON.parse(req.data as string);
+    expect(body.api_token).toBe('secret');
+    expect(body.verify_tls).toBe(false);
+  });
+});
+
+describe('deleteC2Config', () => {
+  it('sends DELETE to correct URL', async () => {
+    mock.onDelete('/engagements/3/c2-config').reply(204);
+    await expect(deleteC2Config(3)).resolves.toBeUndefined();
+    expect(mock.history['delete'][0].url).toBe('/engagements/3/c2-config');
+  });
+});
+
+describe('testC2Config', () => {
+  it('sends POST and returns test result', async () => {
+    mock.onPost('/engagements/1/c2-config/test').reply(200, { ok: true, error: null });
+    const result = await testC2Config(1);
+    expect(result.ok).toBe(true);
+    expect(result.error).toBeNull();
+    expect(mock.history['post'][0].url).toBe('/engagements/1/c2-config/test');
+  });
+
+  it('returns error message when connection fails', async () => {
+    mock
+      .onPost('/engagements/1/c2-config/test')
+      .reply(200, { ok: false, error: 'Connection refused' });
+    const result = await testC2Config(1);
+    expect(result.ok).toBe(false);
+    expect(result.error).toBe('Connection refused');
+  });
+});
+
+describe('listCallbacks', () => {
+  it('sends GET and returns callbacks', async () => {
+    mock.onGet('/engagements/1/c2/callbacks').reply(200, {
+      callbacks: [
+        {
+          display_id: 1,
+          active: true,
+          host: 'WIN-TARGET',
+          user: 'administrator',
+          domain: 'lab.local',
+          last_checkin: '2026-06-10T10:00:00',
+        },
+      ],
+    });
+    const result = await listCallbacks(1);
+    expect(result.callbacks).toHaveLength(1);
+    expect(result.callbacks[0].display_id).toBe(1);
+    expect(result.callbacks[0].host).toBe('WIN-TARGET');
+    expect(mock.history['get'][0].url).toBe('/engagements/1/c2/callbacks');
+  });
+});
+
+describe('executeC2', () => {
+  it('sends POST with callback_display_id and commands', async () => {
+    mock.onPost('/simulations/5/c2/execute').reply(200, {
+      tasks: [
+        { id: 1, mythic_task_display_id: 42, command: 'whoami', status: 'submitted', completed: false },
+      ],
+    });
+    const result = await executeC2(5, {
+      callback_display_id: 1,
+      commands: ['whoami'],
+    });
+    expect(result.tasks).toHaveLength(1);
+    expect(result.tasks[0].command).toBe('whoami');
+    const req = mock.history['post'][0];
+    expect(req.url).toBe('/simulations/5/c2/execute');
+    const body = JSON.parse(req.data as string);
+    expect(body.callback_display_id).toBe(1);
+    expect(body.commands).toEqual(['whoami']);
+  });
+});
diff --git a/frontend/tests/components/C2ConfigCard.test.tsx b/frontend/tests/components/C2ConfigCard.test.tsx
new file mode 100644
index 0000000..cc6e349
--- /dev/null
+++ b/frontend/tests/components/C2ConfigCard.test.tsx
@@ -0,0 +1,135 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+import { screen, waitFor, fireEvent } from '@testing-library/react';
+import MockAdapter from 'axios-mock-adapter';
+import { apiClient } from '@/api/client';
+import { C2ConfigCard } from '@/components/C2ConfigCard';
+import { renderWithProviders } from '../utils';
+
+vi.mock('@/hooks/useAuth', () => ({
+  useAuth: () => ({
+    user: { id: 1, username: 'alice', role: 'admin', created_at: '2026-01-01' },
+    status: 'authenticated',
+    login: vi.fn(),
+    logout: vi.fn(),
+    isAdmin: true,
+    isRedteam: false,
+    isSoc: false,
+    canEditEngagements: true,
+  }),
+}));
+
+let mock: MockAdapter;
+
+beforeEach(() => {
+  mock = new MockAdapter(apiClient);
+});
+
+afterEach(() => {
+  mock.restore();
+  vi.clearAllMocks();
+});
+
+describe('C2ConfigCard — no config (404)', () => {
+  it('renders the card with empty fields when no config exists', async () => {
+    mock.onGet('/engagements/1/c2-config').reply(404);
+    renderWithProviders(<C2ConfigCard engagementId={1} />);
+    // Wait for loading to finish — query resolves to null on 404
+    await waitFor(() => {
+      expect(screen.getByTestId('c2-url-input')).toBeInTheDocument();
+    });
+    expect(screen.getByTestId('c2-token-input')).toBeInTheDocument();
+    expect(screen.getByTestId('c2-verify-tls')).toBeInTheDocument();
+    expect(screen.getByTestId('c2-save-btn')).toBeInTheDocument();
+    // Delete button only shown when has_token
+    expect(screen.queryByTestId('c2-delete-btn')).toBeNull();
+  });
+});
+
+describe('C2ConfigCard — with config (has_token=true)', () => {
+  beforeEach(() => {
+    mock.onGet('/engagements/1/c2-config').reply(200, {
+      has_token: true,
+      url: 'https://mythic.lab:7443',
+      verify_tls: true,
+    });
+  });
+
+  it('shows Replace token affordance when has_token=true', async () => {
+    renderWithProviders(<C2ConfigCard engagementId={1} />);
+    await waitFor(() => {
+      expect(screen.getByText('Replace token')).toBeInTheDocument();
+    });
+    // Token input shows placeholder bullets (readOnly)
+    const tokenInput = screen.getByTestId('c2-token-input') as HTMLInputElement;
+    expect(tokenInput.readOnly).toBe(true);
+    expect(tokenInput.placeholder).toBe('••••••••');
+  });
+
+  it('shows Delete configuration button when has_token=true', async () => {
+    renderWithProviders(<C2ConfigCard engagementId={1} />);
+    await waitFor(() => {
+      expect(screen.getByTestId('c2-delete-btn')).toBeInTheDocument();
+    });
+  });
+
+  it('clicking Replace token makes input editable', async () => {
+    renderWithProviders(<C2ConfigCard engagementId={1} />);
+    await waitFor(() => {
+      expect(screen.getByText('Replace token')).toBeInTheDocument();
+    });
+    fireEvent.click(screen.getByText('Replace token'));
+    await waitFor(() => {
+      const tokenInput = screen.getByTestId('c2-token-input') as HTMLInputElement;
+      expect(tokenInput.readOnly).toBeFalsy();
+    });
+  });
+
+  it('Test connection button is enabled when config exists', async () => {
+    renderWithProviders(<C2ConfigCard engagementId={1} />);
+    await waitFor(() => {
+      expect(screen.getByTestId('c2-test-btn')).not.toBeDisabled();
+    });
+  });
+
+  it('shows Connected on successful test', async () => {
+    mock.onPost('/engagements/1/c2-config/test').reply(200, { ok: true, error: null });
+    renderWithProviders(<C2ConfigCard engagementId={1} />);
+    await waitFor(() => {
+      expect(screen.getByTestId('c2-test-btn')).not.toBeDisabled();
+    });
+    fireEvent.click(screen.getByTestId('c2-test-btn'));
+    await waitFor(() => {
+      expect(screen.getByText('Connected')).toBeInTheDocument();
+    });
+  });
+
+  it('shows error message on failed test', async () => {
+    mock
+      .onPost('/engagements/1/c2-config/test')
+      .reply(200, { ok: false, error: 'Connection refused' });
+    renderWithProviders(<C2ConfigCard engagementId={1} />);
+    await waitFor(() => {
+      expect(screen.getByTestId('c2-test-btn')).not.toBeDisabled();
+    });
+    fireEvent.click(screen.getByTestId('c2-test-btn'));
+    await waitFor(() => {
+      expect(screen.getByText('Connection refused')).toBeInTheDocument();
+    });
+  });
+});
+
+describe('C2ConfigCard — 503 disabled state', () => {
+  it('shows 503 banner and disables all inputs', async () => {
+    mock.onGet('/engagements/1/c2-config').reply(503);
+    renderWithProviders(<C2ConfigCard engagementId={1} />);
+    await waitFor(() => {
+      expect(
+        screen.getByText(/C2 features are disabled/i),
+      ).toBeInTheDocument();
+    });
+    expect(screen.getByTestId('c2-save-btn')).toBeDisabled();
+    expect(screen.getByTestId('c2-url-input')).toBeDisabled();
+    expect(screen.getByTestId('c2-token-input')).toBeDisabled();
+    expect(screen.getByTestId('c2-verify-tls')).toBeDisabled();
+  });
+});
diff --git a/frontend/tests/components/ExecuteViaC2Modal.test.tsx b/frontend/tests/components/ExecuteViaC2Modal.test.tsx
new file mode 100644
index 0000000..bfeafa4
--- /dev/null
+++ b/frontend/tests/components/ExecuteViaC2Modal.test.tsx
@@ -0,0 +1,160 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+import { screen, waitFor, fireEvent } from '@testing-library/react';
+import MockAdapter from 'axios-mock-adapter';
+import { apiClient } from '@/api/client';
+import { ExecuteViaC2Modal } from '@/components/ExecuteViaC2Modal';
+import { renderWithProviders } from '../utils';
+
+vi.mock('@/hooks/useAuth', () => ({
+  useAuth: () => ({
+    user: { id: 1, username: 'alice', role: 'redteam', created_at: '2026-01-01' },
+    status: 'authenticated',
+    login: vi.fn(),
+    logout: vi.fn(),
+    isAdmin: false,
+    isRedteam: true,
+    isSoc: false,
+    canEditEngagements: true,
+  }),
+}));
+
+const CALLBACKS = [
+  {
+    display_id: 1,
+    active: true,
+    host: 'WIN-TARGET',
+    user: 'administrator',
+    domain: 'lab.local',
+    last_checkin: '2026-06-10T10:00:00',
+  },
+  {
+    display_id: 2,
+    active: false,
+    host: 'WIN-DC01',
+    user: 'SYSTEM',
+    domain: 'lab.local',
+    last_checkin: '2026-06-10T09:00:00',
+  },
+];
+
+let mock: MockAdapter;
+
+beforeEach(() => {
+  mock = new MockAdapter(apiClient);
+  mock.onGet('/engagements/42/c2/callbacks').reply(200, { callbacks: CALLBACKS });
+});
+
+afterEach(() => {
+  mock.restore();
+  vi.clearAllMocks();
+});
+
+function renderModal(initialCommands = 'whoami\nipconfig') {
+  const onClose = vi.fn();
+  renderWithProviders(
+    <ExecuteViaC2Modal
+      simulationId={7}
+      engagementId={42}
+      initialCommands={initialCommands}
+      onClose={onClose}
+    />,
+  );
+  return { onClose };
+}
+
+describe('ExecuteViaC2Modal', () => {
+  it('renders modal with title and callback table', async () => {
+    renderModal();
+    expect(screen.getByTestId('c2-modal')).toBeInTheDocument();
+    expect(screen.getByText('Execute via C2')).toBeInTheDocument();
+    await waitFor(() => {
+      expect(screen.getAllByTestId('c2-callback-row')).toHaveLength(2);
+    });
+  });
+
+  it('renders callback rows with mono data', async () => {
+    renderModal();
+    await waitFor(() => {
+      expect(screen.getByText('WIN-TARGET')).toBeInTheDocument();
+      expect(screen.getByText('WIN-DC01')).toBeInTheDocument();
+      expect(screen.getByText('administrator')).toBeInTheDocument();
+    });
+  });
+
+  it('Launch button is disabled before selecting a callback', async () => {
+    renderModal();
+    await waitFor(() => {
+      expect(screen.getAllByTestId('c2-callback-row')).toHaveLength(2);
+    });
+    expect(screen.getByTestId('c2-launch-btn')).toBeDisabled();
+  });
+
+  it('Launch button is disabled when commands are empty', async () => {
+    renderModal('');
+    await waitFor(() => {
+      expect(screen.getAllByTestId('c2-callback-row')).toHaveLength(2);
+    });
+    fireEvent.click(screen.getAllByTestId('c2-callback-row')[0]);
+    expect(screen.getByTestId('c2-launch-btn')).toBeDisabled();
+  });
+
+  it('Launch button enabled after selecting row and having commands', async () => {
+    renderModal('whoami');
+    await waitFor(() => {
+      expect(screen.getAllByTestId('c2-callback-row')).toHaveLength(2);
+    });
+    fireEvent.click(screen.getAllByTestId('c2-callback-row')[0]);
+    expect(screen.getByTestId('c2-launch-btn')).not.toBeDisabled();
+  });
+
+  it('calls executeC2 with correct body and closes modal on success', async () => {
+    mock.onPost('/simulations/7/c2/execute').reply(200, {
+      tasks: [
+        { id: 1, mythic_task_display_id: 10, command: 'whoami', status: 'submitted', completed: false },
+        { id: 2, mythic_task_display_id: 11, command: 'ipconfig', status: 'submitted', completed: false },
+      ],
+    });
+    const { onClose } = renderModal('whoami\nipconfig');
+    await waitFor(() => {
+      expect(screen.getAllByTestId('c2-callback-row')).toHaveLength(2);
+    });
+    fireEvent.click(screen.getAllByTestId('c2-callback-row')[0]);
+    fireEvent.click(screen.getByTestId('c2-launch-btn'));
+    await waitFor(() => {
+      expect(onClose).toHaveBeenCalled();
+    });
+    const req = mock.history['post'][0];
+    const body = JSON.parse(req.data as string);
+    expect(body.callback_display_id).toBe(1);
+    expect(body.commands).toEqual(['whoami', 'ipconfig']);
+  });
+
+  it('shows inline error and keeps modal open on executeC2 failure', async () => {
+    mock.onPost('/simulations/7/c2/execute').reply(500, { error: 'Mythic unreachable' });
+    const { onClose } = renderModal('whoami');
+    await waitFor(() => {
+      expect(screen.getAllByTestId('c2-callback-row')).toHaveLength(2);
+    });
+    fireEvent.click(screen.getAllByTestId('c2-callback-row')[0]);
+    fireEvent.click(screen.getByTestId('c2-launch-btn'));
+    await waitFor(() => {
+      expect(screen.getByText('Mythic unreachable')).toBeInTheDocument();
+    });
+    expect(onClose).not.toHaveBeenCalled();
+  });
+
+  it('Cancel button calls onClose', async () => {
+    const { onClose } = renderModal();
+    await waitFor(() => {
+      expect(screen.getAllByTestId('c2-callback-row')).toHaveLength(2);
+    });
+    fireEvent.click(screen.getByRole('button', { name: /cancel/i }));
+    expect(onClose).toHaveBeenCalled();
+  });
+
+  it('prefills commands textarea from initialCommands', async () => {
+    renderModal('net user\nwhoami /all');
+    const textarea = screen.getByTestId('c2-commands-textarea') as HTMLTextAreaElement;
+    expect(textarea.value).toBe('net user\nwhoami /all');
+  });
+});