CVE-2026-46420 json
setup-php: Command Injection in Repository-Derived PHP Version Resolution
published 2026-05-20 5 mo ago modified 2026-10-24 15 d ago also EUVD-2026-45303 , GHSA-pqwm-q9pv-ph8r
- cvss
- 5.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.0%
- EPSS 2.0% chance of exploitation in 30 days, percentile 80%
- public exploits
- 0
- none known
Summary
setup-php is a GitHub action to set up PHP with extensions, php.ini configuration, coverage drivers, and tools. From 2.25.0 prior to 2.37.1, shivammathur/setup-php resolves the PHP version from repository-controlled files such as .php-version, composer.lock through platform-overrides.php, and composer.json through config.platform.php, and insufficiently constrains those values before incorporating them into generated shell or PowerShell setup scripts, allowing command injection on a GitHub Actions runner when workflows such as pull_request_target check out attacker-controlled contents before invoking setup-php. This issue is fixed in version 2.37.1.
Patch / fix
- github-actions shivammathur/setup-php 2.37.1
- shivammathur setup_php 2.37.1
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 3 mo ago
Exploit prediction
2.01% chance of exploitation in the next 30 days, higher than 80% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.6 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L |
| GitHub | 3.1 | 5.6 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L |
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| github-actions | shivammathur/setup-php | >=2.25.0, <2.37.1 |
2.37.1 |
Affected products
- shivammathur setup-php
Classification
- Weakness
-
- CWE-78 Improper Neutralization of Special Elements used in an OS Command
References
-
github.com
/shivammathur/setup-php/commit/eeef37e059fb5368a5bc8ed8ce45ff54bd39b80b
web, patch
-
github.com
/shivammathur/setup-php/security/advisories/GHSA-pqwm-q9pv-ph8r
web, patch, vendor-advisory
-
github.com
/shivammathur/setup-php/releases/tag/2.37.1
product, release-notes
-
github.com
/shivammathur/setup-php
package
Sources
- CVE List CVE-2026-46420
- GitHub Advisory GHSA-pqwm-q9pv-ph8r
- NVD CVE-2026-46420
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.