CVE-2007-1700: PHP

High severity, CVSS 7.5. EPSS: 9% chance of exploitation in the next 30 days.

The session extension in PHP 4 before 4.4.5, and PHP 5 before 5.2.1, calculates the reference count for the session variables without considering the internal pointer from the session globals, which allows context-dependent attackers to execute arbitrary code via a crafted string in the session_register after unsetting HTTP_SESSION_VARS and _SESSION, which destroys the session data Hashtable.

Affected products

• PHP PHP: version 4.0 only; version 4.0.0 only; version 4.0.1 only; version 4.0.2 only; version 4.0.3 only; version 4.0.4 only; …

Published 2007-03-27. Last modified 2026-06-16.