The `verify_tls` chain is **fully intact** end-to-end :
React `verifyTls` state → `C2ConfigInput.verify_tls` → PUT body → `C2Config.verify_tls` column → `cfg.verify_tls` in API loader → `get_adapter(verify_tls=)` → `MythicAdapter._verify` → `requests.post(verify=self._verify)`.
Mimic is a BAS / red-team lab tool ; the dominant case is a **self-signed Mythic instance**, not a publicly-trusted cert chain. Defaulting `verify=True` is hostile to the actual workflow.
Secondary defect : `urllib3.exceptions.InsecureRequestWarning` is never suppressed (zero hits for `disable_warnings` / `urllib3` in `backend/`). When operators correctly uncheck verify, stderr gets spammed once per HTTP call.
1.**Flip default to `False` at every layer** — model, API fallback, adapter, factory, React state, delete reset.
2.**New migration 0008** : flip `server_default` to `sa.false()`. Existing rows are NOT mutated (their stored boolean is preserved).
3.**Suppress `urllib3.InsecureRequestWarning` ONLY when `verify_tls=False`** — gated inside `MythicAdapter.__init__`. Keeps the warning live for any future code that legitimately verifies.
4.**Add helper text under checkbox** : "Leave unchecked for lab Mythic with self-signed certificates." Operators see why the box matters.
5.**No API contract change** — `C2ConfigInput.verify_tls: boolean` stays required. The fallback in `data.get("verify_tls", False)` only matters for hand-crafted requests.
-`backend/app/services/c2/mythic.py` — line 116 : `verify_tls: bool = True` → `verify_tls: bool = False`, AND add at top of file `import urllib3` + `from urllib3.exceptions import InsecureRequestWarning`, AND inside `__init__` after `self._verify = verify_tls`:
```python
if not verify_tls:
urllib3.disable_warnings(InsecureRequestWarning)
```
- **NEW migration** `backend/migrations/versions/0008_c2_verify_tls_default_false.py` — flip `server_default` to `sa.false()`. Use `op.batch_alter_table("c2_config")` for SQLite compatibility (Mimic uses SQLite per sprint 1 SPEC). Down-migration restores `sa.true()`.
- **Tests** : grep `backend/tests/` for `verify_tls` and flip every assertion that presupposed the old `True` default (likely in `test_c2_config*.py` PUT-without-verify-tls tests and GET-fresh-row tests). Don't add new tests — adapt existing ones.
**Constraints** :
-`pytest` baseline 468/468 must hold (or grow ; never shrink).
-`ruff` + `mypy --strict` clean.
- Migration 0008 must be reversible — round-trip `alembic upgrade head` then `alembic downgrade -1` then `alembic upgrade head` must work on a fresh SQLite DB.
- Don't restructure or refactor anything else. Minimum surface.
## Task B — Frontend (frontend-builder)
**Files** :
-`frontend/src/components/C2ConfigCard.tsx` :
- Line 27 : `useState(true)` → `useState(false)`
- Line 74 (delete handler) : `setVerifyTls(true)` → `setVerifyTls(false)`
- Under the checkbox JSX (around lines 169-182) : add a `<p>` with helper text :
```tsx
<p className="text-[12px] text-charcoal mt-xxs">
Leave unchecked for lab Mythic with self-signed certificates.
</p>
```
(Use the existing DESIGN.md tokens — `text-[12px] text-charcoal` matches the `hint` style on `FormField`. Confirm token name by reading neighboring components first.)
- **Vitest** : if `C2ConfigCard.test.tsx` exists, flip any "starts checked" assertion to "starts unchecked".
- **design-reviewer** : helper-text placement, token compliance, focus ring still works, no regression on the card.
- **spec-reviewer** : verify SPEC.md § Intégration C2 still matches the new defaults (may need a one-line note about lab-mode default ; check before editing).
- PR opened on Gitea ; tasks/pr-body-sprint-10.md drafted by team-lead.
## Operator notes (for PR body)
- This sprint flips a security-relevant default. Production operators who legitimately use a publicly-trusted cert chain will need to explicitly check the box — but the dominant case in this BAS tool is lab Mythic with self-signed, so the new default matches the actual workflow.
- Existing engagements with `verify_tls=true` already stored remain unchanged. They keep their current behaviour. If the operator reported the bug because their existing row has `verify_tls=true`, they will still need to uncheck + save once after this sprint lands.