CVE-2026-73251

Mongoose is an embedded web server and network library. Prior to 7.23, a network attacker can impersonate a TLS server to a Mongoose client configured with a multi-certificate CA bundle. In src/tls_builtin.c, the mg_tls_init() function stores the bundle in tls->ca_bundle_der while tls->ca_der.len remains zero, and mg_tls_recv_cert() uses tls_bundle_find() to accept a Common Name match without calling mg_tls_verify_cert_signature(). A forged self-signed certificate can therefore satisfy hostname and CertificateVerify checks and enable interception, credential disclosure, traffic modification, and malicious responses. This issue is fixed in version 7.23.

CVSS

No CVSS.

References

Link	Resource
https://github.com/cesanta/mongoose/commit/2988bc9df3a5efc9539471cb7455975fa25df483
https://github.com/cesanta/mongoose/releases/tag/7.23
https://github.com/cesanta/mongoose/security/advisories/GHSA-qj6j-2692-v2r8
https://github.com/cesanta/mongoose/security/advisories/GHSA-qj6j-2692-v2r8
https://github.com/cesanta/mongoose/security/advisories/GHSA-qj6j-2692-v2r8
https://github.com/cesanta/mongoose/security/advisories/GHSA-qj6j-2692-v2r8

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-20 18:16

Updated : 2026-09-09 21:19

NVD link : CVE-2026-73251

Mitre link : CVE-2026-73251

CVE.ORG link : CVE-2026-73251

JSON object : View

Products Affected

No product.

CWE

CWE-295

Improper Certificate Validation

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