{"id":"DEBIAN-CVE-2009-3639","details":"The mod_tls module in ProFTPD before 1.3.2b, and 1.3.3 before 1.3.3rc2, when the dNSNameRequired TLS option is enabled, does not properly handle a '\\0' character in a domain name in the Subject Alternative Name field of an X.509 client certificate, which allows remote attackers to bypass intended client-hostname restrictions via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.","modified":"2026-09-22T16:47:25.646964652Z","published":"2009-10-28T14:30:00.217Z","upstream":["CVE-2009-3639"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2009-3639"}],"affected":[{"package":{"name":"proftpd-dfsg","ecosystem":"Debian:12","purl":"pkg:deb/debian/proftpd-dfsg?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.2a-2"}]}],"ecosystem_specific":{"urgency":"low"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2009-3639.json"}},{"package":{"name":"proftpd-dfsg","ecosystem":"Debian:13","purl":"pkg:deb/debian/proftpd-dfsg?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.2a-2"}]}],"ecosystem_specific":{"urgency":"low"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2009-3639.json"}},{"package":{"name":"proftpd-dfsg","ecosystem":"Debian:14","purl":"pkg:deb/debian/proftpd-dfsg?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.2a-2"}]}],"ecosystem_specific":{"urgency":"low"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2009-3639.json"}}],"schema_version":"1.9.0"}