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 crash the host iOS/macOS/tvOS application. If an attacker publishes the 4-byte malformed payload to a shared topic with the RETAIN flag set to true, the MQTT broker will persist the payload. Any time a vulnerable client connects and subscribes to that topic, the broker will automatically push the malformed packet. The app will instantly crash in the background before the user can even interact with it. This effectively "bricks" the mobile application (a persistent DoS) until the retained message is manually wiped from the broker database. This issue has been patched in version 2.2.2.
Configurations

Configuration 1 (hide)

AND
cpe:2.3:a:emqx:cocoamqtt:*:*:*:*:*:swift:*:*
OR cpe:2.3:o:apple:iphone_os:-:*:*:*:*:*:*:*
cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:*

History

07 Apr 2026, 18:04

Type Values Removed Values Added
CPE cpe:2.3:o:apple:iphone_os:-:*:*:*:*:*:*:*
cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:*
cpe:2.3:a:emqx:cocoamqtt:*:*:*:*:*:swift:*:*
First Time Emqx
Apple iphone Os
Emqx cocoamqtt
Apple macos
Apple
References () https://github.com/emqx/CocoaMQTT/commit/010bca6f61b97d726252f61641d331a2bf82b338 - () https://github.com/emqx/CocoaMQTT/commit/010bca6f61b97d726252f61641d331a2bf82b338 - Patch
References () https://github.com/emqx/CocoaMQTT/pull/659 - () https://github.com/emqx/CocoaMQTT/pull/659 - Issue Tracking, Patch
References () https://github.com/emqx/CocoaMQTT/releases/tag/2.2.2 - () https://github.com/emqx/CocoaMQTT/releases/tag/2.2.2 - Release Notes
References () https://github.com/emqx/CocoaMQTT/security/advisories/GHSA-r3fr-7m74-q7g2 - () https://github.com/emqx/CocoaMQTT/security/advisories/GHSA-r3fr-7m74-q7g2 - Exploit, Vendor Advisory

02 Apr 2026, 14:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-04-02 14:16

Updated : 2026-04-07 18:04


NVD link : CVE-2026-30867

Mitre link : CVE-2026-30867

CVE.ORG link : CVE-2026-30867


JSON object : View

Products Affected

apple

  • iphone_os
  • macos

emqx

  • cocoamqtt
CWE
CWE-617

Reachable Assertion