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+# Incident Response Runbook — SecuScan
+
+## 1. Leaked Vault Keys
+
+### Detection
+
+- Check logs for unauthorized access: `grep "vault" logs/secuscan.log`
+- Review audit trail in `backend/secuscan/vault.py` for key usage
+
+### Response Steps
+
+1. **Immediately rotate** the compromised key — set a new `SECUSCAN_VAULT_KEY` in your `.env` file
+2. **Re-encrypt** stored credentials — delete and re-add all vault entries using the new key
+3. **Invalidate** all active sessions by restarting the backend service
+4. **Audit** which reports and scans ran during the exposure window
+5. **Notify** affected users if credentials were accessed
+
+### Verification
+
+```bash
+# Confirm vault config is loaded correctly
+grep "SECUSCAN_VAULT_KEY" .env
+
+# Confirm backend starts without vault errors
+python -m uvicorn backend.secuscan.main:app --reload
+
+# Run vault-related tests
+pytest testing/backend/unit -k "vault" -v
+```
+
+## 2. Compromised Plugins
+
+### Detection
+
+- Review plugin execution logs for anomalous behavior
+- Check files in `plugins/` for unexpected changes
+
+### Response Steps
+
+1. **Isolate** — remove or rename the compromised plugin file immediately
+2. **Preserve logs** before any cleanup: `cp logs/secuscan.log logs/secuscan.log.bak`
+3. **Audit** all scans that used the compromised plugin via scan history
+4. **Restore** plugin from last known clean git commit
+
+### Verification
+
+```bash
+# List plugin files
+ls plugins/
+
+# Disable compromised plugin by moving its directory out of the active plugin tree
+mv plugins/<plugin-name> plugins/<plugin-name>.disabled
+
+# Restore clean plugin from git
+git checkout main -- plugins/<plugin-name>
+
+# Run plugin tests
+pytest testing/backend/unit -k "plugin" -v
+```
+
+## 3. Restoring Clean State
+
+1. Stop all running scans
+2. Rotate all credentials in `.env`
+3. Re-validate plugin files: `git diff main -- plugins/`
+4. Run full test suite: `pytest testing/backend/unit`
+5. Confirm system health before resuming operations