{"id":"CVE-2020-11993","url":"https://www.cyber-defence.io/tools/cve/CVE-2020-11993","generatedAt":"2026-11-05T02:00:59.730Z","title":"Configuring the LogLevel of mod_http2 above \"info\" will mitigate this vulnerability for unpatched servers.","description":"Apache HTTP Server versions 2.4.20 to 2.4.43 When trace/debug was enabled for the HTTP/2 module and on certain traffic edge patterns, logging statements were made on the wrong connection, causing concurrent use of memory pools. Configuring the LogLevel of mod_http2 above \"info\" will mitigate this vulnerability for unpatched servers.","published":"2020-08-07T16:15:12.000Z","lastModified":"2026-06-17T02:51:13.000Z","status":"Analyzed","sourceIdentifier":"security@apache.org","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-444"],"affected":["apache/http server","netapp/clustered data ontap","canonical/ubuntu linux","opensuse/leap","debian/debian linux","fedoraproject/fedora","oracle/communications element manager","oracle/communications session report manager","oracle/communications session route manager","oracle/enterprise manager ops center","oracle/hyperion infrastructure technology","oracle/instantis enterprisetrack","oracle/zfs storage appliance kit"],"epss":{"score":0.56448,"percentile":0.99058,"date":"2026-11-03","history":[]},"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 56.4%, higher than 99% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00068.html","tags":["Mailing List","Third Party Advisory"],"source":"security@apache.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00071.html","tags":["Mailing List","Third Party Advisory"],"source":"security@apache.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00081.html","tags":["Mailing List","Third Party Advisory"],"source":"security@apache.org"},{"url":"http://packetstormsecurity.com/files/160393/Apache-2-HTTP2-Module-Concurrent-Pool-Usage.html","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"security@apache.org"},{"url":"https://httpd.apache.org/security/vulnerabilities_24.html#CVE-2020-11993","tags":["Vendor 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Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ITVFDBVM6E3JF3O7RYLRPRCH3RDRHJJY/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202008-04","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20200814-0005/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4458-1/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2020/dsa-4757","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com/security-alerts/cpujan2021.html","tags":["Third Party 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