CVE-2007-4657: Canonical Ubuntu Linux

High severity, CVSS 7.5. EPSS: 3% chance of exploitation in the next 30 days.

Multiple integer overflows in PHP 4 before 4.4.8, and PHP 5 before 5.2.4, allow remote attackers to obtain sensitive information (memory contents) or cause a denial of service (thread crash) via a large len value to the (1) strspn or (2) strcspn function, which triggers an out-of-bounds read. NOTE: this affects different product versions than CVE-2007-3996.

Affected products

• Canonical Ubuntu Linux: version 6.06 only; version 6.10 only; version 7.04 only; version 7.10 only
• Debian Debian Linux: version 3.1 only; version 4.0 only
• PHP PHP: from 4.0.0, before 4.4.8 (fixed in 4.4.8); from 5.0.0, before 5.2.4 (fixed in 5.2.4)

Published 2007-09-04. Last modified 2026-06-16.