{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-73257","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-08-11T17:18:01.598Z","datePublished":"2026-08-20T17:30:58.424Z","dateUpdated":"2026-08-20T19:34:58.840Z"},"containers":{"cna":{"title":"Mongoose: Content-Length + Transfer-Encoding coexistence enables request smuggling","problemTypes":[{"descriptions":[{"cweId":"CWE-444","lang":"en","description":"CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":9.1,"baseSeverity":"CRITICAL","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"}}],"references":[{"name":"https://github.com/cesanta/mongoose/security/advisories/GHSA-5wfq-r6mr-wqp6","tags":["x_refsource_CONFIRM"],"url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-5wfq-r6mr-wqp6"},{"name":"https://github.com/cesanta/mongoose/pull/3611","tags":["x_refsource_MISC"],"url":"https://github.com/cesanta/mongoose/pull/3611"},{"name":"https://github.com/cesanta/mongoose/commit/a9df523f76f43a38bd53b4232b9cfd4c16869e71","tags":["x_refsource_MISC"],"url":"https://github.com/cesanta/mongoose/commit/a9df523f76f43a38bd53b4232b9cfd4c16869e71"},{"name":"https://github.com/cesanta/mongoose/releases/tag/7.22","tags":["x_refsource_MISC"],"url":"https://github.com/cesanta/mongoose/releases/tag/7.22"}],"affected":[{"vendor":"cesanta","product":"mongoose","versions":[{"version":"< 7.22","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-08-20T17:30:58.424Z"},"descriptions":[{"lang":"en","value":"Mongoose is an embedded web server and network library. Priro to version 7.22, a remote unauthenticated attacker can send an HTTP request containing both Content-Length and Transfer-Encoding: chunked. The cl_count and te_count checks in the mg_http_parse() and http_cb() paths in src/http.c accept both headers and prioritize chunked encoding, while a Content-Length-preferring reverse proxy can use a different request boundary. This CL.TE desynchronization can inject requests that access or modify resources in another user context. This issue is fixed in version 7.22."}],"source":{"advisory":"GHSA-5wfq-r6mr-wqp6","discovery":"UNKNOWN"}},"adp":[{"references":[{"url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-5wfq-r6mr-wqp6","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-20T19:34:52.897430Z","id":"CVE-2026-73257","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-08-20T19:34:58.840Z"}}]}}