High 7.4Published Nov 6, 2025

CVE-2025-12790Rubygem-mqtt: rubygem-mqtt hostname validation

Updated under an hour ago (Oct 27, 2026, 11:23 PM ET)

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It affects Nicholas J Humfrey ruby-mqtt and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Nicholas J Humfrey ruby-mqtt

Exploited in the last 30 days

A flaw was found in Rubygem MQTT. By default, the package used to not have hostname validation, resulting in possible Man-in-the-Middle (MITM) attack.

CVSS: 7.4 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Weakness (CWE): CWE-29
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: redhat
NVD analysis: Deferred
Record last updated: Feb 26, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Nicholas J Humfrey ruby-mqtt nicholas_j_humfrey:ruby_mqtt (from the name)	before 0.7.0	CNA record
Red Hat Red Hat Satellite 6 redhat:satellite	6	CNA record

References

References

https://access.redhat.com/security/cve/CVE-2025-12790	vdb-entry, x-refsource-redhat
https://bugzilla.redhat.com/show_bug.cgi?id=2413004	issue-tracking, x-refsource-redhat
https://github.com/njh/ruby-mqtt/blob/main/NEWS.md#ruby-mqtt-version-070-2025-10-29

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.