{"schemaVersion":3,"id":"CVE-2026-86247","aliases":["UBUNTU-CVE-2026-86247","DEBIAN-CVE-2026-86247"],"status":"published","duplicateOf":null,"title":null,"description":"Race condition within a thread vulnerability in Apache Tomcat Native allowed client certificate verification requirements to be down-graded for some configurations.\n\n\n\nThis issue affects Apache Tomcat Native: from 2.0.0 through 2.0.15, from 1.3.0 through 1.3.8. Unsupported versions may also be affected.\n\n\n\nUsers are recommended to upgrade to version 2.0.16 or 1.3.9, which fixes the issue.","dates":{"published":"2026-09-23T12:31:53.210Z","modified":"2026-09-23T18:10:50.704Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":7.4,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":7.4,"severity":"high","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Ubuntu","score":7.4,"severity":"high","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","exploitability":5.6,"impact":8.7,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · 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