CVE-2026-5244: A vulnerability has been found in Cesanta Mongoose up to 7.20. This affects the function mg_tls_recv_cert of the file…
CVE-2026-5244 · Severity: high · CVSS 7.3 · Published 2026-04-02
A vulnerability has been found in Cesanta Mongoose up to 7.20. This affects the function mg_tls_recv_cert of the file mongoose.c of the component TLS 1.3 Handler. Such manipulation of the argument pubkey leads to heap-based buffer overflow. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 7.21 mitigates this issue. The name of the patch is 0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1. It is advisable to upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.
No. Junglewise Threat Intelligence has no report of CVE-2026-5244 being exploited in the wild.
How severe is CVE-2026-5244?
High severity, with a CVSS score of 7.3, published 2 April 2026.
Which products and versions are affected?
Cesanta Mongoose. The advisory does not name versions.
Is there a fix for CVE-2026-5244?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2026-5244?
Check whether you run Cesanta Mongoose. 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.