CVE-2025-65953 NanoMQ UAF of retain message due to invalid MQTTV5 properties
A heap use-after-free in NanoMQ allows attackers to execute code or cause denial of service via malformed MQTTV5 retain messages.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-65953?
CVE-2025-65953 is a medium-severity use after free vulnerability in nanomq, published on 25 Nov 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Prior to version 0.22.5, a Heap-Use-After-Free (UAF) vulnerability exists in the TCP transport component of NanoMQ, which relies on the underlying NanoNNG library (specifically in src/sp/transport/mqtt/broker_tcp.c). The vulnerability is due to improper resource management and premature cleanup of message and pipe structures under specific malformed MQTTV5 retain message traffic conditions. This issue has been patched in version 0.22.5.
Weakness: CWE-416
Which versions are affected by CVE-2025-65953?
How do I fix CVE-2025-65953?
No fix has been published for CVE-2025-65953 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2025-65953 being exploited?
There is no known exploitation of CVE-2025-65953 in the wild and no public exploit code.
Sources
Also known as GHSA-r95p-wjm8-2qxr.