{"id":"DEBIAN-CVE-2018-12551","details":"When Eclipse Mosquitto version 1.0 to 1.5.5 (inclusive) is configured to use a password file for authentication, any malformed data in the password file will be treated as valid. This typically means that the malformed data becomes a username and no password. If this occurs, clients can circumvent authentication and get access to the broker by using the malformed username. In particular, a blank line will be treated as a valid empty username. Other security measures are unaffected. Users who have only used the mosquitto_passwd utility to create and modify their password files are unaffected by this vulnerability.","modified":"2026-09-01T16:04:37.851558242Z","published":"2019-03-27T18:29:00.367Z","upstream":["CVE-2018-12551"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2018-12551"}],"affected":[{"package":{"name":"mosquitto","ecosystem":"Debian:12","purl":"pkg:deb/debian/mosquitto?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.5.6-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2018-12551.json"}},{"package":{"name":"mosquitto","ecosystem":"Debian:13","purl":"pkg:deb/debian/mosquitto?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.5.6-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2018-12551.json"}},{"package":{"name":"mosquitto","ecosystem":"Debian:14","purl":"pkg:deb/debian/mosquitto?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.5.6-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2018-12551.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}