VULNERABILITY INTELLIGENCE
CVE-2009-4418
CVSS score5 MEDIUM
EPSS probability0.97%
CISA KEVNot currently listed
Published2009-12-24
Last modified2026-06-16
CVSS vectorAV:N/AC:L/Au:N/C:N/I:N/A:P
Description
The unserialize function in PHP 5.3.0 and earlier allows context-dependent attackers to cause a denial of service (resource consumption) via a deeply nested serialized variable, as demonstrated by a string beginning with a:1: followed by many {a:1: sequences.