{"cve":"CVE-2018-12551","nvd":{"published":"2019-03-27T18:29:00.367","modified":"2026-06-17T01:37:57.813","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.0","vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.1},"cwes":["CWE-287","CWE-703"],"references":["https://bugs.eclipse.org/bugs/show_bug.cgi?id=543401","https://lists.debian.org/debian-lts-announce/2019/10/msg00035.html","https://bugs.eclipse.org/bugs/show_bug.cgi?id=543401","https://lists.debian.org/debian-lts-announce/2019/10/msg00035.html"],"products":["eclipse:mosquitto"],"source":"nvd","synced_at":"2026-10-19T20:55:22.313337056+00:00"},"epss":{"cve":"CVE-2018-12551","score":0.01475,"percentile":0.73841,"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."]}