VULNERABILITY INTELLIGENCE
CVE-2009-4142
CVSS score4.3 MEDIUM
EPSS probability6.50%
CISA KEVNot currently listed
Published2009-12-21
Last modified2026-06-16
CVSS vectorAV:N/AC:M/Au:N/C:N/I:P/A:N
Description
The htmlspecialchars function in PHP before 5.2.12 does not properly handle (1) overlong UTF-8 sequences, (2) invalid Shift_JIS sequences, and (3) invalid EUC-JP sequences, which allows remote attackers to conduct cross-site scripting (XSS) attacks by placing a crafted byte sequence before a special character.
Weakness classification
- CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')