{"id":"UBUNTU-CVE-2026-73257","details":"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.","modified":"2026-10-17T13:01:01.923539105Z","published":"2026-08-20T18:16:00Z","upstream":["CVE-2026-73257"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-73257"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-73257"}],"affected":[{"package":{"name":"mongoose","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/mongoose?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7.21+ds-1","7.21+ds-2","7.22+ds-1","7.23+ds-1"],"ecosystem_specific":{"binaries":[{"binary_version":"7.23+ds-1","binary_name":"mongoose-webserver-source"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-73257.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"},{"type":"Ubuntu","score":"medium"}]}