CVE-2026-5246: A vulnerability was determined in Cesanta Mongoose up to 7.20. Affected is the function mg_tls_verify_cert_signature…
CVE-2026-5246 · Severity: medium · CVSS 5.6 · Published 2026-04-02
A vulnerability was determined in Cesanta Mongoose up to 7.20. Affected is the function mg_tls_verify_cert_signature of the file mongoose.c of the component P-384 Public Key Handler. Executing a manipulation can lead to authorization bypass. The attack can be executed remotely. Attacks of this nature are highly complex. The exploitability is told to be difficult. The exploit has been publicly disclosed and may be utilized. Upgrading to version 7.21 is able to address this issue. This patch is called 0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1. The affected component should be upgraded. 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-2026-5246 being exploited in the wild.
How severe is CVE-2026-5246?
Medium severity, with a CVSS score of 5.6, published 2 April 2026.
Which products and versions are affected?
Cesanta Mongoose. The advisory does not name versions.
Is there a fix for CVE-2026-5246?
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-2026-5246?
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.