{"id":"CVE-2026-73252","published":"2026-10-14T19:17:19.667","lastModified":"2026-10-16T20:04:29.760","description":"Mongoose is an embedded web server and network library. Prior to 7.23, the built-in TLS stack selected by MG_TLS_BUILTIN in src/tls_builtin.c accepts a TLS 1.3 record whose decrypted size is exactly the 16-byte authentication tag with no plaintext or ContentType byte. In mg_tls_recv_record(), the msgsz length check permits that record and the recv_len calculation underflows to SIZE_MAX, so a later handshake step treats stale buffer contents as a trusted message with an effectively unbounded length. An unauthenticated malicious TLS peer can trigger a heap out-of-bounds read before certificate or Finished validation, causing a remote denial of service. This issue is fixed in version 7.23.","cvssScore":7.5,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwes":["CWE-125","CWE-191"],"vendors":[],"products":[],"references":[{"url":"https://github.com/cesanta/mongoose/commit/758e301f0c9a9885c1b716195df5fe6d6ac9d53e","tags":[]},{"url":"https://github.com/cesanta/mongoose/releases/tag/7.23","tags":[]},{"url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-hq58-98f5-2wg3","tags":[]},{"url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-hq58-98f5-2wg3","tags":[]}],"exploitRefs":[{"url":"https://github.com/cesanta/mongoose/commit/758e301f0c9a9885c1b716195df5fe6d6ac9d53e","tags":[]},{"url":"https://github.com/cesanta/mongoose/releases/tag/7.23","tags":[]},{"url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-hq58-98f5-2wg3","tags":[]},{"url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-hq58-98f5-2wg3","tags":[]}],"hasPoc":true,"ai":null}