{"schema":"threatline.record/2","record":{"id":"CVE-2026-73252","aliases":["GHSA-hq58-98f5-2wg3"],"summary":"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","details":"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.","categories":["Unclassified"],"product":"mongoose","vendor":"cesanta","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-73252","source_modified_at":"2026-10-14T19:41:57.801Z","fetched_at":"2026-10-23T18:48:36.087640Z","product":"mongoose","vendor":"cesanta","versions":[{"status":"affected","version":"< 7.23"}],"defaultStatus":null},{"source":"GitHub Advisory Database","source_url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-hq58-98f5-2wg3","source_modified_at":"2026-08-12T13:48:21Z","fetched_at":"2026-10-23T22:01:05.715934Z","package":{"ecosystem":"c","name":"mongoose"},"range":"<= 7.22"}],"fixed_versions":[{"source":"GitHub Advisory Database","source_url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-hq58-98f5-2wg3","source_modified_at":"2026-08-12T13:48:21Z","fetched_at":"2026-10-23T22:01:05.715934Z","package":{"ecosystem":"c","name":"mongoose"},"version":"7.23"}],"cvss":7.5,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00376,"percentile":0.30413,"score_date":"2026-10-23"},"published_at":"2026-10-14T18:24:16.659Z","modified_at":"2026-10-14T19:41:57.801Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-73252","fetched_at":"2026-10-23T18:48:36.087640Z","source_modified_at":"2026-10-14T19:41:57.801Z"},{"source":"GitHub Advisory Database","url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-hq58-98f5-2wg3","fetched_at":"2026-10-23T22:01:05.715934Z","source_modified_at":"2026-08-12T13:48:21Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-73252","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","GitHub Advisory Database","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-hq58-98f5-2wg3","tags":["exploit"]},{"source":"CVE List","url":"https://github.com/cesanta/mongoose/commit/758e301f0c9a9885c1b716195df5fe6d6ac9d53e","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/cesanta/mongoose/releases/tag/7.23","tags":["x_refsource_MISC"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"poc","automatable":"yes","technical_impact":"partial","assessed_at":"2026-10-14T19:41:34.958467Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-14T19:41:57.801Z","content_hash":"32685eb67dfe80721032d45ecfac643048b9b33e863875e7602abd951e4e4ba6"}}