{"cve":"CVE-2009-0580","nvd":{"published":"2009-06-05T16:00:00.233","modified":"2026-06-16T23:05:20.887","status":"Modified","description":"Apache Tomcat 4.1.0 through 4.1.39, 5.5.0 through 5.5.27, and 6.0.0 through 6.0.18, when FORM authentication is used, allows remote attackers to enumerate valid usernames via requests to /j_security_check with malformed URL encoding of passwords, related to improper error checking in the (1) MemoryRealm, (2) DataSourceRealm, and (3) JDBCRealm authentication realms, as demonstrated by a % (percent) value for the j_password parameter.","cvss_v4":null,"cvss_v3":null,"cwes":["CWE-200"],"references":["http://lists.apple.com/archives/security-announce/2010//Mar/msg00001.html","http://lists.opensuse.org/opensuse-security-announce/2009-07/msg00002.html","http://marc.info/?l=bugtraq&m=127420533226623&w=2","http://marc.info/?l=bugtraq&m=129070310906557&w=2","http://marc.info/?l=bugtraq&m=133469267822771&w=2"],"products":["apache:tomcat"],"source":"nvd","synced_at":"2026-10-19T19:54:07.895733559+00:00"},"epss":{"cve":"CVE-2009-0580","score":0.9444,"percentile":0.99852,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-w227-xcfx-3pj8","url":"https://osv.dev/vulnerability/GHSA-w227-xcfx-3pj8","summary":"Exposure of Sensitive Information in Apache Tomcat","modified":"2023-11-08T03:56:52.663629Z","packages":[{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","purl":"pkg:maven/org.apache.tomcat/tomcat","ranges":[">=4.1.0 <4.1.40"],"fixed":["4.1.40"]},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","purl":"pkg:maven/org.apache.tomcat/tomcat","ranges":[">=5.0.0 <5.5.28"],"fixed":["5.5.28"]},{"ecosystem":"Maven","name":"org.apache.tomcat:tomcat","purl":"pkg:maven/org.apache.tomcat/tomcat","ranges":[">=6.0.0 <6.0.19"],"fixed":["6.0.19"]}]}],"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."]}