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GitHub actions/checkout blocks fork pull request checkouts by default in privileged workflows

Security Tool/Service
First reported
Last updated
Happening score
H score 11
1 unique sources, 1 articles

Summary

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GitHub's actions/checkout now refuses common pwn request patterns by default, cutting the risk of attacker-controlled code execution in privileged GitHub Actions workflows. The guardrail applies to forked pull requests in pull_request_target and related workflow_run paths that can expose secrets and GITHUB_TOKEN access. The change began on June 18, 2026 and will be backported to supported major versions on July 16, 2026.

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Timeline

  1. 23.06.2026 17:22 2 articles · 1h ago

    actions/checkout v7 blocks fork pull request checkouts in privileged workflows

    Mitigation Patch Update

    GitHub's actions/checkout v7 began refusing fork pull request checkouts by default in pull_request_target and certain workflow_run workflows, blocking common pwn request patterns unless workflow authors set allow-unsafe-pr-checkout to true.

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  2. 23.06.2026 17:22 1 articles · 1h ago

    GitHub announces default refusal of fork pull request code in actions/checkout

    Initial Disclosure

    GitHub announced that actions/checkout is being updated to block pwn request abuse of pull_request_target by refusing fork pull request checkouts that can run attacker-controlled code with the base repository's GITHUB_TOKEN, secrets, and write privileges.

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  3. 23.06.2026 17:22 1 articles · 1h ago

    GitHub plans July 16 backport of fork pull request checkout refusal

    Mitigation Patch Update

    GitHub expects to backport the same fork pull request checkout refusal in actions/checkout to all currently supported major versions on July 16, 2026, extending the guardrail beyond the latest release.

    Show sources