{"cve":"CVE-2009-5017","nvd":{"published":"2010-11-12T22:00:01.923","modified":"2026-06-16T23:14:50.163","status":"Modified","description":"Mozilla Firefox before 3.6 Beta 3 does not properly handle overlong UTF-8 encoding, which makes it easier for remote attackers to bypass cross-site scripting (XSS) protection mechanisms via a crafted string, a different vulnerability than CVE-2010-1210.","cvss_v4":null,"cvss_v3":null,"cwes":["CWE-79"],"references":["http://hg.mozilla.org/releases/mozilla-1.9.2/rev/e42c563313a0","http://sirdarckcat.blogspot.com/2009/10/couple-of-unicode-issues-on-php-and.html","https://bugzilla.mozilla.org/show_bug.cgi?id=511859","https://bugzilla.mozilla.org/show_bug.cgi?id=522634","http://hg.mozilla.org/releases/mozilla-1.9.2/rev/e42c563313a0"],"products":["mozilla:firefox"],"source":"nvd","synced_at":"2026-10-19T19:57:56.749847046+00:00"},"epss":{"cve":"CVE-2009-5017","score":0.01831,"percentile":0.78877,"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."]}