== SLACK SIGNATURE VALIDATION LOG ==
Captured from backend kubectl logs: 2026-05-23 UTC
Incident: b9abfcc7-1078-44f9-bffd-c2c54628d8a6

== REQUEST RECEIVED ==
2026-05-23 13:31:06 [info] webhooks.slack.request_received
  client=10.42.0.29
  client_ip=54.210.161.182
  client_origin=forwarded_external
  forwarded_for=54.210.161.182
  forwarded_for_present=True
  forwarded_host=app.oncallzero.com
  host=app.oncallzero.com
  path=/webhooks/slack/actions
  slack_signature_header_present=True
  slack_timestamp_header_present=True
  tunnel_provider=
  user_agent='Slackbot 1.0 (+https://api.slack.com/robots)'

== SIGNATURE VALID ==
2026-05-23 13:31:06 [info] webhooks.slack.signature_valid
  client_ip=54.210.161.182
  clock_skew_seconds=0
  forwarded_host=app.oncallzero.com
  host=app.oncallzero.com
  path=/webhooks/slack/actions
  signature_validation_reason=valid
  slack_signature_header_present=True
  slack_timestamp_header_present=True
  tunnel_provider=

== CALLBACK RECEIVED ==
2026-05-23 13:31:06 [info] webhooks.slack.callback_received
  action_id=approve_action
  client_ip=54.210.161.182
  client_origin=forwarded_external
  decision_key=approve
  forwarded_host=app.oncallzero.com
  host=app.oncallzero.com
  incident_id=b9abfcc7-1078-44f9-bffd-c2c54628d8a6
  path=/webhooks/slack/actions
  slack_signature_header_present=True
  slack_timestamp_header_present=True
  tunnel_provider=
  user_agent='Slackbot 1.0 (+https://api.slack.com/robots)'
  user_id=U0AKT8RE8N9
  username=khmuraandriy

== VERDICT ==
Slack signature: VALID (clock_skew_seconds=0, signature_validation_reason=valid)
Tunnel provider: NONE (direct Slack delivery to app.oncallzero.com)
Slack callback host: app.oncallzero.com
Client IP: 54.210.161.182 (Slack IP range)
Approver: khmuraandriy (U0AKT8RE8N9)
Allowlisted user IDs: ["U0AKT8RE8N9"] (configured in SLACK_APPROVED_USER_IDS)

NOTE: SLACK_SIGNING_SECRET and SLACK_APPROVED_USER_IDS values are redacted.
Backend log confirms: slack_signing_secret_configured=True