CVE-2011-1398: PHP

Medium severity, CVSS 4.3. EPSS: 10.2% chance of exploitation in the next 30 days.

The sapi_header_op function in main/SAPI.c in PHP before 5.3.11 and 5.4.x before 5.4.0RC2 does not check for %0D sequences (aka carriage return characters), which allows remote attackers to bypass an HTTP response-splitting protection mechanism via a crafted URL, related to improper interaction between the PHP header function and certain browsers, as demonstrated by Internet Explorer and Google Chrome.

Affected products

• PHP PHP: up to and including 5.3.10; version 5.3.0 only; version 5.3.1 only; version 5.3.2 only; version 5.3.3 only; version 5.3.4 only; …

Published 2012-08-30. Last modified 2026-06-16.