9.8
CRITICAL CVSS 3.1
CVE-2026-46420
setup-php: Command Injection in Repository-Derived PHP Version Resolution
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.

INFO

Published Date :

July 17, 2026, 8:17 p.m.

Last Modified :

Aug. 18, 2026, 3:54 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-46420 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Shivammathur setup_php
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM [email protected]
CVSS 3.1 CRITICAL [email protected]
Solution
Update setup-php to version 2.37.1 to prevent command injection.
  • Update setup-php to version 2.37.1 or later.
  • Ensure PHP versions are properly validated.
Public PoC/Exploit Available at Github

CVE-2026-46420 has a 2 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-46420.

URL Resource
https://github.com/shivammathur/setup-php/commit/eeef37e059fb5368a5bc8ed8ce45ff54bd39b80b Patch
https://github.com/shivammathur/setup-php/releases/tag/2.37.1 Product Release Notes
https://github.com/shivammathur/setup-php/security/advisories/GHSA-pqwm-q9pv-ph8r Patch Vendor Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-46420 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

PoC for CVE-2026-46420, command injection in shivammathur/setup-php via repository-controlled PHP version resolution.

command-injection cwe-78 github-actions poc security-research setup-php cve-2026-46420

Updated: 1 month, 3 weeks ago
1 stars 0 fork 0 watcher
Born at : July 18, 2026, 10:27 p.m. This repo has been linked 1 different CVEs too.

📡 PoC auto collect from GitHub. ⚠️ Be careful Malware.

security cve exploit poc vulnerability

Updated: 1 month, 3 weeks ago
7922 stars 1275 fork 1275 watcher
Born at : Dec. 8, 2019, 1:03 p.m. This repo has been linked 646 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-46420 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-46420 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    Aug. 18, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CPE Configuration OR *cpe:2.3:a:shivammathur:setup_php:*:*:*:*:*:*:*:* versions from (including) 2.25.0 up to (excluding) 2.37.1
    Added Reference Type GitHub, Inc.: https://github.com/shivammathur/setup-php/commit/eeef37e059fb5368a5bc8ed8ce45ff54bd39b80b Types: Patch
    Added Reference Type GitHub, Inc.: https://github.com/shivammathur/setup-php/releases/tag/2.37.1 Types: Product, Release Notes
    Added Reference Type GitHub, Inc.: https://github.com/shivammathur/setup-php/security/advisories/GHSA-pqwm-q9pv-ph8r Types: Patch, Vendor Advisory
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jul. 20, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-46420', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-20T18:09:22.675511Z'}
  • New CVE Received by [email protected]

    Jul. 17, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'shivammathur', 'product': 'setup-php', 'versions': [{'status': 'affected', 'version': '>= 2.25.0, < 2.37.1'}]}]
    Added 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.
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
    Added CWE CWE-78
    Added Reference https://github.com/shivammathur/setup-php/commit/eeef37e059fb5368a5bc8ed8ce45ff54bd39b80b
    Added Reference https://github.com/shivammathur/setup-php/releases/tag/2.37.1
    Added Reference https://github.com/shivammathur/setup-php/security/advisories/GHSA-pqwm-q9pv-ph8r
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.