CVE-2023-27581 json
github-slug-action vulnerable to arbitrary code execution
published 2023-03-13 3 y ago modified 2026-09-10 1 mo ago also EUVD-2023-0908 , GHSA-6q4m-7476-932w
- cvss
- 8.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.6%
- EPSS 1.6% chance of exploitation in 30 days, percentile 75%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- github-actions rlespinasse/github-slug-action 4.4.1
- github-slug-action_project github-slug-action 4.4.1
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 20 mo ago
Exploit prediction
1.58% chance of exploitation in the next 30 days, higher than 75% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- securitylab.github.com https://securitylab.github.com/research/github-actions-untrusted-input/ referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| GitHub | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| github-actions | rlespinasse/github-slug-action | >=4.0.0, <4.4.1 |
4.4.1 |
Affected products
- rlespinasse github-slug-action
Classification
- Weakness
-
- CWE-77 Improper Neutralization of Special Elements used in a Command
References
-
github.com
/rlespinasse/github-slug-action/commit/102b1a064a9b145e56556e22b18b19c624538d94
web, patch
-
securitylab.github.com
/research/github-actions-untrusted-input/
exploit, third-party-advisory
-
github.com
/rlespinasse/github-slug-action/security/advisories/GHSA-6q4m-7476-932w
web, vendor-advisory
-
github.com
/rlespinasse/github-slug-action/releases/tag/v4.4.1
web, release-notes
-
nvd.nist.gov
/vuln/detail/CVE-2023-27581
advisory
-
github.com
/rlespinasse/github-slug-action
package
-
securitylab.github.com
/research/github-actions-untrusted-input
web
Sources
- CVE List CVE-2023-27581
- GitHub Advisory GHSA-6q4m-7476-932w
- NVD CVE-2023-27581
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.