CVE-2026-46420

CRITICAL
INFO Priority: 0.20 BB Relevance: 80/100
Published: 2026-07-17 Modified: 2026-10-24 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: High
I: High
A: High

Description

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.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
shivammathur setup_php 2.25.0 – 2.37.1

Bug Bounty Relevance

80 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

9.8 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploitation Probability

2.01%
Raw Score 0.020100
Percentile 80.8%
Date 2026-10-29

EPSS Trend

2026-10-29
0.02010
2026-10-28
0.02010

Intelligence Sources

nvd ref →