Quick answers
- Is CVE-2026-44640 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-44640 being exploited in the wild.
- How severe is CVE-2026-44640?
- Medium severity, with a CVSS score of 4.5, published 29 May 2026.
- Which products and versions are affected?
- EMQ NanoMQ < 0.24.14.
- Is there a fix for CVE-2026-44640?
- A patch was published on 2026-05-29: Version 0.24.14 released with fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-44640 attacked?
- It is attacked with local access, in a software library.
- Am I affected by CVE-2026-44640?
- Check whether you run EMQ NanoMQ at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A type confusion vulnerability exists in NanoMQ's QUIC implementation within `nng/src/supplemental/quic/msquic_dial.c`. During the dialing process, the `aio->prov_data` field is populated with a pointer of type `nni_quic_conn*`; however, during the dialer close path, the code incorrectly attempts to read this data as an `ex_quic_conn*`. This incompatible type interpretation leads to invalid memory access, resulting in a process hang or crash (Denial of Service). Exploitation requires specific timing during the connection phase and is categorized as having high complexity. The issue is resolved in version 0.24.14.
Affected products
- EMQ NanoMQ < 0.24.14
Timeline
- 2026-05-19: advisory: GitHub Security Advisory published
- 2026-05-29: patched: Version 0.24.14 released with fix
- 2026-05-29: disclosed: CVE-2026-44640 published to NVD