CVE-2009-2191: Apple Mac OS X

High severity, CVSS 7.5. EPSS: 4.2% chance of exploitation in the next 30 days.

Format string vulnerability in Login Window in Apple Mac OS X 10.4.11 and 10.5 before 10.5.8 allows attackers to execute arbitrary code or cause a denial of service (application crash) via format string specifiers in an application name.

Affected products

• Apple Mac OS X: version 10.5.6 only; version 10.4.11 only; version 10.5 only; version 10.5.7 only
• Apple Mac OS X Server: version 10.4.11 only; version 10.5.5 only; version 10.5.6 only; version 10.5.7 only

Published 2009-08-06. Last modified 2026-06-16.