{"schemaVersion":3,"id":"CVE-2026-77756","aliases":["UBUNTU-CVE-2026-77756","DEBIAN-CVE-2026-77756"],"status":"published","duplicateOf":null,"title":null,"description":"Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat caused by processing the transfer-encoding header for an HTTP/1.0 request may allow an attacker to cause one request from another user to fail when Tomcat is located behind a reverse proxy.\n\n\n\nThis issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.47 through 9.0.121.\n\n\n\nThe following versions were EOL at the time the CVE was created but are\nknown to be affected: from 8.5.67 through 8.5.100. Other unsupported versions may also be affected.\n\n\n\nUsers are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.","dates":{"published":"2026-09-23T11:18:02.672Z","modified":"2026-09-23T18:10:42.842Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":3.7,"severity":"low","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":3.7,"severity":"low","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Ubuntu","score":3.7,"severity":"low","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","exploitability":5.6,"impact":2.3,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · 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