What is CVE-2018-12546?

CVE-2018-12546 is a medium-severity vulnerability in Eclipse Mosquitto, classified under Improper Access Control. CVSS score: 6.5/10. Published 2019-03-27.

How severe is CVE-2018-12546?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Vulnerability in Eclipse Mosquitto

CVE-2018-12546

In Eclipse Mosquitto version 1.0 to 1.5.5 (inclusive) when a client publishes a retained message to a topic, then has its access to that topic revoked, the retained message will still be published to clients that subscribe to that topic in the future. In some applications this may result in clients being able cause effects that would otherwise not be allowed.

Published 2019-03-27 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.008 (54.9th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 54.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Eclipse Mosquitto
The Eclipse Foundation Mosquitto — versions 1.0, unspecified

Weakness classification (CWE)

References

bugs.eclipse.org/bugs/show_bug.cgi (Exploit, Issue Tracking, Vendor Advisory)

Frequently asked questions

What is CVE-2018-12546?: CVE-2018-12546 is a medium-severity vulnerability in Eclipse Mosquitto, classified under Improper Access Control. CVSS score: 6.5/10. Published 2019-03-27.
How severe is CVE-2018-12546?: Medium severity. CVSS v3 base score is 6.5 out of 10.