CVE-2018-12550: eclipse mosquitto Expected Behavior Violation
Vulnerability summary
CVE-2018-12550 is a high (CVSS 8.1) Expected Behavior Violation vulnerability in eclipse mosquitto. EPSS estimates a 1.35% chance of exploitation in the next 30 days, higher than 71.1% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 3 · Related 1Timeline
- 27-03-2019PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
When Eclipse Mosquitto version 1.0 to 1.5.5 (inclusive) is configured to use an ACL file, and that ACL file is empty, or contains only comments or blank lines, then Mosquitto will treat this as though no ACL file has been defined and use a default allow policy. The new behaviour is to have an empty ACL file mean that all access is denied, which is not a useful configuration but is not unexpected.
CVSS metrics
5 scores · 4 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated8.1HighCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · UbuntuEcosystem advisory · calculated8.1HighCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated8.1HighCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
1.35%
Chance of exploitation in the next 30 days
Percentile
71%
Versus all other CVEs
30-day change
0.00 pp
From 1.35% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Alpine1 product
- mosquitto≥ 1.0, < 1.5.6-r0 | ≥ 1.0, < 1.4.15-r1 | ≥ 1.0, < 1.4.15-r4
Debian1 product
- mosquitto< 1.5.6-1
Eclipse1 product
- mosquitto≥ 1.0, ≤ 1.5.5
The eclipse foundation1 product
- eclipse mosquitto≥ 1.0, < unspecified | ≥ unspecified, ≤ 1.5.5
Ubuntu1 product
- mosquittoAll versions (No fix recorded) | < 1.4.8-1ubuntu0.16.04.5 | < 1.4.15-2ubuntu0.18.04.1
5 vendors · 5 products
