What is CVE-2026-30867?

CVE-2026-30867 is a medium-severity vulnerability in Emqx Cocoamqtt, classified under Reachable Assertion. CVSS score: 5.7/10. Published 2026-04-02.

How severe is CVE-2026-30867?

Medium severity. CVSS v3 base score is 5.7 out of 10.

Vulnerability in Emqx Cocoamqtt

CVE-2026-30867

CocoaMQTT is a MQTT 5.0 client library for iOS and macOS written in Swift. Prior to version 2.2.2, a vulnerability exists in the packet parsing logic of CocoaMQTT that allows an attacker (or a compromised/malicious MQTT broker) to remotely…

EPSS: 0.000 (4.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.7 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H.

Affected products

Emqx Cocoamqtt — versions < 2.2.2

Weakness classification (CWE)

CWE-617 — Reachable Assertion

References

https://github.com/emqx/CocoaMQTT/security/advisories/GHSA-r3fr-7m74-q7g2 (x_refsource_CONFIRM)
https://github.com/emqx/CocoaMQTT/pull/659 (x_refsource_MISC)
https://github.com/emqx/CocoaMQTT/commit/010bca6f61b97d726252f61641d331a2bf82b338 (x_refsource_MISC)
https://github.com/emqx/CocoaMQTT/releases/tag/2.2.2 (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-30867?: CVE-2026-30867 is a medium-severity vulnerability in Emqx Cocoamqtt, classified under Reachable Assertion. CVSS score: 5.7/10. Published 2026-04-02.
How severe is CVE-2026-30867?: Medium severity. CVSS v3 base score is 5.7 out of 10.