The escapeshellarg function in ext/standard/exec.c in PHP before 5.4.42, 5.5.x before 5.5.26, and 5.6.x before 5.6.10 on Windows allows remote attackers to execute arbitrary OS commands via a crafted string to an application that accepts command-line arguments for a call to the PHP system function.
Severity
CVSS 3.0
9.8 critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
6.0% chance of exploitation in the next 30 days; higher than 93% of CVEs (scores of 2026-10-31)