CVE-2026-46420

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.

CVSS 3.1

9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

2.0% chance of exploitation in the next 30 days; higher than 80% of CVEs (scores of 2026-10-25)

CWE

CWE-78

Published

2026-07-17

Modified

2026-10-24

Record from

the NVD, synced 2026-10-25

Affected

• shivammathur:setup_php

References

• https://github.com/shivammathur/setup-php/commit/eeef37e059fb5368a5bc8ed8ce45ff54bd39b80b
• https://github.com/shivammathur/setup-php/releases/tag/2.37.1
• https://github.com/shivammathur/setup-php/security/advisories/GHSA-pqwm-q9pv-ph8r

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