check-spelling workflow vulnerable to token leakage via symlink attack

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.6 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N

EPSS

• CVE-2021-32724: 2.33% estimated exploitation activity in the next 30 days; percentile 83.59 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact For a repository with the check-spelling action enabled that triggers on pullrequesttarget (or schedule), an attacker can send a crafted Pull Request that causes a GITHUBTOKEN to be exposed. With the GITHUBTOKEN, it's possible to push commits to the repository bypassing standard approval processes. Commits to the repository could then steal any/all secrets available to the repository. Workarounds You can either: Disable the workflow until you've fixed all branches. or Set repository to Allow specific actions. You can check: - [x] Allow actions created by GitHub - [x] Allow Marketplace actions by verified creators check-spelling isn't a verified creator and it certainly won't be anytime soon. You could then explicitly add other actions that your repository uses. or Set repository Workflow permissions to Read repository contents permission. Solution Workflows using check-spelling/check-spelling@main were fixed automatically with the release of v0.0.19. Workflows using a pinned…

Published by the source

29 Jul 2022, 19:56 UTC

Last modified by the source

27 Jan 2023, 05:07 UTC

Source last checked

26 Oct 2026, 17:08 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-g86g-chm8-7r2p

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# Patch Next advisory brief: CVE-2021-32724

Advisory: check-spelling workflow vulnerable to token leakage via symlink attack
IDs: CVE-2021-32724, GHSA-g86g-chm8-7r2p
Record: https://patchnext.com/advisories/cve-2021-32724 (revision 1, source checked 26 Oct 2026, 17:08 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.6)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: check-spelling/check-spelling 0.0.19. A vendor fix does not mean a deployment is fixed.

## Affected components
- GitHub Actions check-spelling/check-spelling: affected < 0.0.19; fixed in 0.0.19

## Suggested inspection (read-only)
- GitHub Actions check-spelling/check-spelling: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on check-spelling/check-spelling.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-g86g-chm8-7r2p (GitHub-reviewed advisory GHSA-g86g-chm8-7r2p lists affected ranges: GitHub Actions check-spelling/check-spelling >=0 <0.0.19)

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