CVE-2023-27581
github-slug-action is a GitHub Action to expose slug value of GitHub environment variables inside of one's GitHub workflow.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.58%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
github-slug-action is a GitHub Action to expose slug value of GitHub environment variables inside of one's GitHub workflow. Starting in version 4.0.0` and prior to version 4.4.1, this action uses the `github.head_ref` parameter in an insecure way. This vulnerability can be triggered by any user on GitHub on any workflow using the action on pull requests. They just need to create a pull request with a branch name, which can contain the attack payload. This can be used to execute code on the GitHub runners and to exfiltrate any secrets one uses in the CI pipeline. A patched action is available in version 4.4.1. No workaround is available.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.58% probability · 75th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-77
- Affected
- github-slug-action project/github-slug-action
- Source
- security-advisories@github.com
EPSS 1.6% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/rlespinasse/github-slug-action/commit/102b1a064a9b145e56556e22b18b19c624538d94Patch
- https://github.com/rlespinasse/github-slug-action/releases/tag/v4.4.1Release Notes
- https://github.com/rlespinasse/github-slug-action/security/advisories/GHSA-6q4m-7476-932wVendor Advisory
- https://securitylab.github.com/research/github-actions-untrusted-input/Exploit, Third Party Advisory
- https://github.com/rlespinasse/github-slug-action/commit/102b1a064a9b145e56556e22b18b19c624538d94Patch
- https://github.com/rlespinasse/github-slug-action/releases/tag/v4.4.1Release Notes
- https://github.com/rlespinasse/github-slug-action/security/advisories/GHSA-6q4m-7476-932wVendor Advisory
- https://securitylab.github.com/research/github-actions-untrusted-input/Exploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.