Trust only our own comments for the state marker#51
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read_state_marker accepted a marker from any comment, so anyone able to comment on a public repo could plant one; if its base matched, the resume would merge an attacker-chosen commit (fork-pushed objects are reachable by hash) into the branch and push it with the action's token. A quote-reply of an old conflict comment could likewise resurrect a stale marker, since HTML comments survive quoting and the newest marker wins. Filter the comments to viewerDidAuthor, i.e. those posted with the same token the action runs under. Also reject markers with missing fields instead of passing empty values to git: a marker missing squash= used to crash the run on update-ref and strand the PR under the label. 🤖 Generated with [Claude Code](https://claude.com/claude-code) https://claude.ai/code/session_01JHvKryT4QUpHYdNq9YEQxX
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read_state_markeraccepted a marker from any comment, so on a public repo anyone able to comment could plant one; if itsbase=matched, the resume would merge an attacker-chosen commit (fork-pushed objects are reachable by hash in the repo network) into the branch and push it with the action's token. Benign variant: a quote-reply of an old conflict comment resurrects a stale marker, since HTML comments survive quoting and the newest marker wins.Fix: filter comments to
viewerDidAuthor— those posted with the same token the action runs under — which needs no configured identity. The resume test's gh mock rejects comment queries without that filter. Caveat: if the repo switches tokens (e.g.GITHUB_TOKEN→ App) while a PR sits in conflict, the old marker is no longer "ours" and the resume takes the safe abandon path.Also rejects markers with missing fields instead of passing empty values to git (a marker missing
squash=used to crash onupdate-refand strand the PR under the label); new scenario E covers it.Stacked on #50 (same function).
🤖 Generated with Claude Code
https://claude.ai/code/session_01JHvKryT4QUpHYdNq9YEQxX
Generated by Claude Code