CVE-2006-5178: PHP

Medium severity, CVSS 6.2. EPSS: 0.7% chance of exploitation in the next 30 days.

Race condition in the symlink function in PHP 5.1.6 and earlier allows local users to bypass the open_basedir restriction by using a combination of symlink, mkdir, and unlink functions to change the file path after the open_basedir check and before the file is opened by the underlying system, as demonstrated by symlinking a symlink into a subdirectory, to point to a parent directory via .. (dot dot) sequences, and then unlinking the resulting symlink.

Affected products

• PHP PHP: up to and including 5.1.6; version 4.0 only; version 4.0.1 only; version 4.0.2 only; version 4.0.3 only; version 4.0.4 only; …

Published 2006-10-10. Last modified 2026-06-16.