VULNERABILITY INTELLIGENCE

CVE-2003-1564

CVSS score6.5 MEDIUM
EPSS probability1.62%
CISA KEVNot currently listed
Published2003-12-31
Last modified2026-06-16
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Description

libxml2, possibly before 2.5.0, does not properly detect recursion during entity expansion, which allows context-dependent attackers to cause a denial of service (memory and CPU consumption) via a crafted XML document containing a large number of nested entity references, aka the "billion laughs attack."

Weakness classification

  • CWE-776: Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')

Primary references