CVE-2011-4203: Moodle

Medium severity, CVSS 5.0. EPSS: 1% chance of exploitation in the next 30 days.

CRLF injection vulnerability in calendar/set.php in the Calendar component in Moodle 1.9.x before 1.9.15, 2.0.x before 2.0.6, 2.1.x before 2.1.3, and 2.2 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via vectors involving the url variable.

Affected products

• Moodle Moodle: version 1.9.1 only; version 1.9.2 only; version 1.9.3 only; version 1.9.4 only; version 1.9.5 only; version 1.9.6 only; …

Published 2011-12-22. Last modified 2026-06-16.