{"id":"CVE-2026-111808","state":"PUBLISHED","title":"Apache Traffic Server: HTTP/2 DATA frame padding underflow lets a client trigger backend worker-pool exhaustion","description":"Apache Traffic Server can be used to exhaust an HTTP/1.1 origin's worker pool via a malformed padded HTTP/2 DATA frame.\n\n\n\nThis issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.15, from 10.0.0 through 10.1.4, 10.2.0.\n\n\n\nUsers are recommended to upgrade to version 9.2.16, 10.1.5, or 10.2.1, which fix the issue.","publishedAt":"2026-10-21T19:11:59.516Z","updatedAt":"2026-10-23T21:22:09.150Z","severity":{"score":7.7,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:H","source":"apache"},"assigner":"apache","products":["Apache Software Foundation Apache Traffic Server"],"affected":[{"vendor":"Apache Software Foundation","product":"Apache Traffic 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