CVE-2026-41570 | PHPUnit: Argument injection via newline in PHP INI values forwarded to child processes

PHPUnit is a testing framework for PHP. In versions 12.5.21 and 13.1.5, PHPUnit forwards PHP INI settings to child processes (used for isolated/PHPT test execution) as -d name=value command-line arguments without neutralizing INI metacharacters. Because PHP's INI parser interprets " as a string delimiter, ; as the start of a comment, and most importantly a newline as a directive separator, a value containing a newline is parsed by the child process as multiple INI directives. An attacker able to influence a single INI value can therefore inject arbitrary additional directives into the child's configuration, including auto_prepend_file, extension, disable_functions, open_basedir, and others. Setting auto_prepend_file to an attacker-controlled path yields remote code execution in the child process. This issue has been patched in versions 12.5.22 and 13.1.6.

Published: 2026-05-08 Last update: 2026-05-08 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-41570 is rated Low Risk (38.4/100): CVSS High severity, with low exploitation likelihood (EPSS 0.07%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-41570

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-09 0.07%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-41570

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 5.9 [email protected]

Weakness enumeration for CVE-2026-41570

GitHub Security Advisory for CVE-2026-41570

GHSA-qrr6-mg7r-m243 · Severity: high · Ecosystem: composer — PHPUnit has Argument injection via newline in PHP INI values that are forwarded to child processes

OS Trackers for CVE-2026-41570

vendor priority summary link
debian unimportant CVE-2026-41570 unimportant priority: Debian including 1 source packages (phpunit), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-41570
ubuntu medium CVE-2026-41570 medium priority: Ubuntu including 1 source packages (phpunit), 8 status rows across 8 suites (bionic, focal, jammy, noble, questing, resolute, upstream, xenial): needs-triage 8. https://ubuntu.com/security/CVE-2026-41570

Affected software / configurations for CVE-2026-41570

Vendor Product Version Raw CPE
phpunit_project phpunit 12.5.21 cpe:2.3:a:phpunit_project:phpunit:12.5.21:*:*:*:*:-:*:*
phpunit_project phpunit 13.1.5 cpe:2.3:a:phpunit_project:phpunit:13.1.5:*:*:*:*:-:*:*

References for CVE-2026-41570

cvelogic Threat Intelligence