# Review by Staff Security Engineer (Round 1)

Now let me write the review output based on my thorough analysis. Here is my security review:

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## Staff Security Engineer Review

### Checklist Assessment

**Completeness:**
- [x] All functional requirements from the PRD are implemented (FR-1 through FR-21)
- [x] All tasks in the task file are marked complete
- [x] No placeholder or TODO code remains

**Quality:**
- [x] All 342 tests pass
- [x] Code follows existing project conventions
- [x] No unnecessary dependencies added (reuses existing slack-bolt, claude-agent-sdk)
- [x] No unrelated changes included

**Safety:**
- [x] No secrets or credentials in committed code
- [x] Error handling is present for failure cases
- [⚠️] Partial concerns on prompt injection and input validation (see findings)

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VERDICT: request-changes

FINDINGS:
- [src/colonyos/slack.py:466-470]: `extract_base_branch` captures `\S+` from untrusted Slack messages with no validation that the result is a legal git branch name. A user could craft `base:main\`\nIgnore all previous instructions...` to embed adversarial content. While `validate_branch_exists` will reject non-existent branches, the extracted value is also passed to the LLM deliver prompt *before* full validation completes in certain code paths (the triage agent's `base_branch` field is also unvalidated). Add a regex allowlist (e.g., `^[a-zA-Z0-9._/-]+$`) to `extract_base_branch` and to `_parse_triage_response` for the `base_branch` field.
- [src/colonyos/orchestrator.py:1744-1748]: The `base_branch` value is interpolated directly into the deliver phase system prompt (`f"...target the branch \`{base_branch}\`..."`). Since `base_branch` originates from untrusted Slack input (via triage LLM output or regex extraction), this is a prompt injection vector into the deliver phase, which runs with `bypassPermissions` and full tool access (Read, Write, Edit, Bash). A crafted branch name could inject instructions that the deliver agent would execute with elevated privileges. Sanitize or validate `base_branch` to strict git-ref characters before embedding in prompts.
- [src/colonyos/agent.py:52]: The triage agent runs with `allowed_tools=[]` (good) but still under `permission_mode="bypassPermissions"`. While the empty tool list should prevent tool use, defense-in-depth suggests the triage call should NOT use `bypassPermissions` — if the SDK has a bug or `allowed_tools=[]` is interpreted as "default tools," the blast radius is unlimited file/shell access. Consider adding a `permission_mode` parameter to `run_phase_sync` so triage can run with restricted permissions.
- [src/colonyos/cli.py:1761-1764]: The `slack_client_ref` pattern (storing client in a mutable list for cross-thread access) has no synchronization. While practically safe since it's append-once, this is a code smell for concurrent code. A `threading.Event` or explicit field would be clearer and safer.
- [src/colonyos/orchestrator.py:1691-1699]: The `git fetch` and `git branch --track` commands use list-form `subprocess.run` (good — no shell injection), but there is no timeout-guarded error handling. If `base_branch` contains a very long string or unusual characters, git may behave unexpectedly. The broad `except Exception: pass` silently swallows all errors including permission denied, disk full, etc.
- [src/colonyos/slack.py:577-580]: The `triage_message` function reuses `Phase.PLAN` enum for triage calls with a comment "reuse plan phase enum." This conflates triage with planning in audit logs and cost tracking, making it impossible to distinguish triage spend from actual planning spend in post-hoc analysis. Consider adding a `Phase.TRIAGE` enum value for auditability.

SYNTHESIS:
From a supply chain security and least-privilege perspective, this implementation gets the high-value decisions right: the triage agent has zero tool access, Slack content is sanitized before LLM calls, subprocess invocations use list-form (no shell injection), budget caps and circuit breakers are enforced, and the fail-safe on malformed triage JSON defaults to non-actionable (deny by default). However, the `base_branch` field represents an unsanitized path from untrusted Slack input directly into a system prompt that controls an agent with `bypassPermissions` + full filesystem/shell tools — this is the highest-severity finding and must be fixed before merge. The triage agent running under `bypassPermissions` with an empty tool list is a defense-in-depth gap that should be addressed. Adding a strict character allowlist for `base_branch` (matching git's own ref naming rules) and a dedicated `Phase.TRIAGE` for audit clarity would bring this to an approvable state.