CVE-2017-9841 — PHPUnit Command Injection Vulnerability

Overview

PHPUnit allows remote attackers to execute arbitrary PHP code via HTTP POST data beginning with a "<?php " substring, as demonstrated by an attack on a site with an exposed /vendor folder, i.e., external access to the /vendor/phpunit/phpunit/src/Util/PHP/eval-stdin.php URI.

Vulnerability details

CVE ID

CVE-2017-9841

Vulnerability

PHPUnit Command Injection Vulnerability

Vendor

PHPUnit

Affected products

PHPUnit: PHPUnit

Severity

HIGH

Exploitation status

Actively exploited in the wild (CISA KEV)

Published

2022-02-15

Remediation guidance

CVE-2017-9841 is in CISA's Known Exploited Vulnerabilities (KEV) catalog — U.S. federal civilian agencies are required to remediate it under Binding Operational Directive 22-01. Treat it as a priority for every environment.

Apply the vendor's official security update for PHPUnit the affected product as soon as possible. Where a patch is unavailable, apply vendor mitigations or isolate/segment exposed systems.

Hunt for indicators of compromise tied to this vulnerability and confirm logging/EDR coverage on affected assets.

Authoritative references

• NVD — National Vulnerability Database
• MITRE CVE Record
• CISA Known Exploited Vulnerabilities Catalog
• FIRST EPSS — Exploit Prediction Scoring