CVE-2024-42651 Use after free in n/a

High 7.5 Published 29 Jul 2025 Updated 29 Jul 2025

Attackers can cause a Denial of Service in NanoMQ by sending a crafted SUBSCRIBE message that triggers a heap use-after-free.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2024-42651?

CVE-2024-42651 is a high-severity use after free vulnerability in n/a, published on 29 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

NanoMQ v0.17.9 was discovered to contain a heap use-after-free vulnerability via the component sub_Ctx_handle. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted SUBSCRIBE message.

Weakness: CWE-400

Which versions are affected by CVE-2024-42651?

It affects 1 product.

Products include Emqx Nanomq.

How do I fix CVE-2024-42651?

No fix has been published for CVE-2024-42651 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-2024-42651 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2024-42651 exists.

Sources

Also known as GHSA-fx4f-94f8-r3jm.