CVE-2026-30867

See a problem?
Please try reporting it to the source first.
Source
https://cve.org/CVERecord?id=CVE-2026-30867
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-30867.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-30867
Aliases
Published
2026-04-02T13:57:06Z
Modified
2026-08-12T03:51:44Z
Severity
  • 5.7 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H CVSS Calculator
Summary
CocoaMQTT: Denial of Service via Reachable Assertion in `PUBLISH` Packet Parsing
Details

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.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-617"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/30xxx/CVE-2026-30867.json"
}
References

Affected packages

Git / github.com/emqx/cocoamqtt

Affected ranges

Type
GIT
Repo
https://github.com/emqx/cocoamqtt
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
3a3062c5be99f5bdb983656d18860119b831da26
Fixed
010bca6f61b97d726252f61641d331a2bf82b338
Database specific
Show details 
{
    "cpe": "cpe:2.3:a:emqx:cocoamqtt:*:*:*:*:*:swift:*:*",
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "2.2.2"
        }
    ],
    "source": [
        "CPE_RANGE",
        "REFERENCES"
    ]
}

Affected versions

0.*
0.1
0.1.1
1.*
1.0-beta
1.0.0
1.0.10
1.0.11
1.0.12
1.0.13
1.0.14
1.0.15
1.0.16
1.0.17
1.0.18
1.0.19
1.0.20
1.0.3
1.0.4
1.0.5
1.0.6
1.0.7
1.0.8
1.0.9
1.1.0
1.1.1
1.1.2
1.2.0
1.2.1
1.3.0-alpha.1
1.3.0-alpha.2
1.3.0-rc.2
2.*
2.0.0
2.0.1
2.0.2
2.0.2-beta1
2.0.2-beta2
2.0.2-beta3
2.0.2-beta4
2.0.2-beta5
2.0.2-beta6
2.0.3-beta1
2.0.3-beta2
2.0.3-beta3
2.0.3-beta4
2.0.3-beta5
2.0.3-beta6
2.0.3-beta7
2.0.4
2.0.5
2.0.6
2.0.7
2.0.8
2.0.9
2.1.0
2.1.1
2.1.2
2.1.3
2.1.4
2.1.5
2.1.6
2.1.7
2.1.8
2.1.9
2.2.0
2.2.1

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-30867.json"