Critical 9.8Published Apr 2, 2026

CVE-2026-5244A vulnerability has been found in Cesanta Mongoose up to 7.20.

Updated under an hour ago (2026-10-19 11:10 UTC)

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Every CVE for cesanta mongoose

Exploited in the last 30 days

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.

CVSS: 9.8 CRITICAL (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-119, CWE-122
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Analyzed
Record last updated: Jun 17, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

cesanta mongoose cesanta:mongoose	from 7.0 before 7.21	NVD

References

https://github.com/cesanta/mongoose/product
https://github.com/cesanta/mongoose/commit/0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1patch
https://github.com/cesanta/mongoose/releases/tag/7.21product, release-notes
https://vuldb.com/submit/770063exploit, third-party-advisory, vdb-entry
https://vuldb.com/vuln/354825third-party-advisory, vdb-entry
https://vuldb.com/vuln/354825/ctipermissions-required, vdb-entry

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.