{"cve":"CVE-2009-4142","nvd":{"published":"2009-12-21T16:30:00.343","modified":"2026-06-16T23:13:07.173","status":"Modified","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.","cvss_v4":null,"cvss_v3":null,"cwes":["CWE-79"],"references":["http://bugs.php.net/bug.php?id=49785","http://lists.apple.com/archives/security-announce/2010//Mar/msg00001.html","http://marc.info/?l=bugtraq&m=127680701405735&w=2","http://secunia.com/advisories/37821","http://secunia.com/advisories/38648"],"products":["php:php"],"source":"nvd","synced_at":"2026-10-19T19:55:32.599380760+00:00"},"epss":{"cve":"CVE-2009-4142","score":0.06497,"percentile":0.93767,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}