{"id":"CVE-2018-11763","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-11763","generatedAt":"2026-10-29T04:48:43.616Z","title":"In Apache HTTP Server 2.4.17 to 2.4.34, by sending continuous, large SETTINGS frames a client can occupy a connection, server thread and CPU time without any connection timeout coming to effect.","description":"In Apache HTTP Server 2.4.17 to 2.4.34, by sending continuous, large SETTINGS frames a client can occupy a connection, server thread and CPU time without any connection timeout coming to effect. This affects only HTTP/2 connections. A possible mitigation is to not enable the h2 protocol.","published":"2018-09-25T21:29:00.000Z","lastModified":"2026-06-17T01:36:32.000Z","status":"Modified","sourceIdentifier":"security@apache.org","cvss":{"version":"3.0","score":5.9,"severity":"MEDIUM","vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":[],"affected":["apache/http server","canonical/ubuntu linux","redhat/enterprise linux","oracle/enterprise manager ops center","oracle/hospitality guest access","oracle/instantis enterprisetrack","oracle/retail xstore point of service","oracle/secure global desktop","netapp/storage automation store"],"epss":{"score":0.50847,"percentile":0.98921,"date":"2026-10-28","history":[{"date":"2026-09-21","score":0.45263,"percentile":0.9877},{"date":"2026-09-22","score":0.50847,"percentile":0.98874}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"EPSS puts the probability of exploitation in the next 30 days at 50.8%, higher than 99% of all known CVEs. Patch or mitigate before the next change window."},"changes":[{"kind":"epss","label":"EPSS jump","at":"2026-09-22T00:00:00.000Z","detail":{"to":0.50847,"from":0.45263,"percentile":0.98874},"summary":"EPSS moved from 45.3% to 50.8% probability of exploitation in the next thirty days."}],"references":[{"url":"http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00030.html","source":"security@apache.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00056.html","source":"security@apache.org"},{"url":"http://www.securityfocus.com/bid/105414","tags":["Third Party Advisory","VDB Entry"],"source":"security@apache.org"},{"url":"http://www.securitytracker.com/id/1041713","tags":["Third Party Advisory","VDB Entry"],"source":"security@apache.org"},{"url":"https://access.redhat.com/errata/RHSA-2018:3558","tags":["Third Party Advisory"],"source":"security@apache.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:0366","tags":["Third Party 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Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03909en_us","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/3783-1/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com/technetwork/security-advisory/cpujan2019-5072801.html","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.tenable.com/security/tns-2019-09","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-11763","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}