Improper Certificate Validation Affecting mongoose package, versions <7.23+ds-1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-DEBIANUNSTABLE-MONGOOSE-18778388
- published14 Aug 2026
- disclosed20 Aug 2026
Introduced: 14 Aug 2026
NewCVE-2026-73251 (opens in a new tab)How to fix?
Upgrade Debian:unstable mongoose to version 7.23+ds-1 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream mongoose package and not the mongoose package as distributed by Debian.
See How to fix? for Debian:unstable relevant fixed versions and status.
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.