# Review by Staff Security Engineer (Round 4)

VERDICT: approve

FINDINGS:
- [src/colonyos/orchestrator.py:1502-1508]: `_extract_review_findings_summary` blank-line handling is correct — blank lines between findings don't stop collection. However, the parser's state machine has a minor edge: a line starting with `-` but not `- ` (e.g., `--- separator ---`) would trigger `break` via the `not stripped.startswith("-")` check. This is correct behavior (stops at non-finding content) but worth noting for future reviewers.
- [src/colonyos/orchestrator.py:420-428]: `_format_task_list_with_descriptions` silently swallows `ValueError`/`TypeError` on cost/duration formatting. Adding `logger.debug` would cost nothing and aid future debugging — but this is a style nit, not a security concern.

SYNTHESIS:
This implementation is production-ready from a security perspective. All three non-blocking findings from round 3 have been addressed: the bare-link regex now covers arbitrary URI schemes (not just http/https), audit logging fires when content is neutralized, and the phase header truncation uses the named constant consistently. The sanitization architecture is sound — `sanitize_untrusted_content()` strips XML injection at the outer boundary, `sanitize_for_slack()` neutralizes Slack-specific injection vectors (mentions, links, mrkdwn formatting, blockquotes), and the ordering is correct and consistently applied at all 7 ingress points. The truncation layer provides secondary defense against information leakage. The 135-test suite includes dedicated integration tests verifying the sanitization chain end-to-end through the formatting functions. All 135 tests pass. No remaining security concerns warrant blocking. Ship it.

Review artifact saved to `cOS_reviews/reviews/staff_security_engineer/20260331_201500_round4_when_you_output_followups_in_the_thread_on_slack_a938599349.md`.
