{"id":"CVE-2026-73252","revision":"d171a3adc1634bc4b14c8a54c4d3fdf2","records":[{"revision":"d171a3adc1634bc4b14c8a54c4d3fdf2","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-73252","aliases":[],"title":"Mongoose: Unauthenticated remote heap out-of-bounds read in built-in TLS: off-by-one length check in mg_tls_recv_record() underflows recv_len to SIZE_MAX","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.","state":0,"publishedAt":"2026-10-14T18:24:16.659+00:00","modifiedAt":"2026-10-14T19:41:57.801+00:00","affected":[{"ecosystem":"Vendor product","name":"mongoose","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"cesanta\",\n                    \"product\": \"mongoose\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 7.23\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://github.com/cesanta/mongoose/security/advisories/GHSA-hq58-98f5-2wg3","https://github.com/cesanta/mongoose/commit/758e301f0c9a9885c1b716195df5fe6d6ac9d53e","https://github.com/cesanta/mongoose/releases/tag/7.23"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-73252","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-73252","identifiers":["CVE-2026-73252"]},"retained":false,"historicalAffected":[]}],"coverage":[]}