{"id":"CVE-2023-50868","url":"https://www.cyber-defence.io/tools/cve/CVE-2023-50868","generatedAt":"2026-10-27T23:58:23.967Z","title":"The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance is skipped) allows remote attackers to cause a denial of service (CPU consumption for SHA-1 computations) via DNSSEC responses in a random subdomain attack, aka…","description":"The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance is skipped) allows remote attackers to cause a denial of service (CPU consumption for SHA-1 computations) via DNSSEC responses in a random subdomain attack, aka the \"NSEC3\" issue. The RFC 5155 specification implies that an algorithm must perform thousands of iterations of a hash function in certain situations.","published":"2024-02-14T16:15:45.000Z","lastModified":"2026-06-17T06:40:07.000Z","status":"Analyzed","sourceIdentifier":"cve@mitre.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-400"],"affected":["netapp/hci baseboard management controller","netapp/active iq unified manager","netapp/bootstrap os","powerdns/recursor","redhat/enterprise linux","debian/debian linux","fedoraproject/fedora","isc/bind"],"epss":{"score":0.74295,"percentile":0.99486,"date":"2026-10-26","history":[{"date":"2026-09-29","score":0.73725,"percentile":0.99462}]},"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 74.3%, higher than 99% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"http://www.openwall.com/lists/oss-security/2024/02/16/2","tags":["Issue Tracking","Mailing List"],"source":"cve@mitre.org"},{"url":"http://www.openwall.com/lists/oss-security/2024/02/16/3","tags":["Issue Tracking","Mailing List"],"source":"cve@mitre.org"},{"url":"https://access.redhat.com/security/cve/CVE-2023-50868","tags":["Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://bugzilla.suse.com/show_bug.cgi?id=1219826","tags":["Issue Tracking"],"source":"cve@mitre.org"},{"url":"https://datatracker.ietf.org/doc/html/rfc5155","tags":["Technical Description"],"source":"cve@mitre.org"},{"url":"https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2024-01.html","tags":["Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://gitlab.nic.cz/knot/knot-resolver/-/releases/v5.7.1","tags":["Release Notes"],"source":"cve@mitre.org"},{"url":"https://kb.isc.org/docs/cve-2023-50868","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2024/02/msg00006.html","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2024/05/msg00011.html","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6FV5O347JTX7P5OZA6NGO4MKTXRXMKOZ/","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BUIP7T7Z4T3UHLXFWG6XIVDP4GYPD3AI/","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HVRDSJVZKMCXKKPP6PNR62T7RWZ3YSDZ/","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IGSLGKUAQTW5JPPZCMF5YPEYALLRUZZ6/","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PNNHZSZPG2E7NBMBNYPGHCFI4V4XRWNQ/","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RGS7JN6FZXUSTC2XKQHH27574XOULYYJ/","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SVYA42BLXUCIDLD35YIJPJSHDIADNYMP/","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TEXGOYGW7DBS3N2QSSQONZ4ENIRQEAPG/","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UQESRWMJCF4JEYJEAKLRM6CT55GLJAB7/","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/","tags":["Mailing List","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2024q1/017430.html","tags":["Mailing List","Release Notes"],"source":"cve@mitre.org"},{"url":"https://nlnetlabs.nl/news/2024/Feb/13/unbound-1.19.1-released/","tags":["Release Notes"],"source":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20240307-0008/","tags":["Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://www.isc.org/blogs/2024-bind-security-release/","tags":["Exploit","Mitigation","Press/Media Coverage"],"source":"cve@mitre.org"},{"url":"http://www.openwall.com/lists/oss-security/2024/02/16/2","tags":["Issue Tracking","Mailing List"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.openwall.com/lists/oss-security/2024/02/16/3","tags":["Issue Tracking","Mailing List"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/security/cve/CVE-2023-50868","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bugzilla.suse.com/show_bug.cgi?id=1219826","tags":["Issue Tracking"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://datatracker.ietf.org/doc/html/rfc5155","tags":["Technical Description"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2024-01.html","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://gitlab.nic.cz/knot/knot-resolver/-/releases/v5.7.1","tags":["Release Notes"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://kb.isc.org/docs/cve-2023-50868","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2024/02/msg00006.html","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2024/05/msg00011.html","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2024/09/msg00001.html","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2024/11/msg00035.html","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6FV5O347JTX7P5OZA6NGO4MKTXRXMKOZ/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BUIP7T7Z4T3UHLXFWG6XIVDP4GYPD3AI/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HVRDSJVZKMCXKKPP6PNR62T7RWZ3YSDZ/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IGSLGKUAQTW5JPPZCMF5YPEYALLRUZZ6/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PNNHZSZPG2E7NBMBNYPGHCFI4V4XRWNQ/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RGS7JN6FZXUSTC2XKQHH27574XOULYYJ/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SVYA42BLXUCIDLD35YIJPJSHDIADNYMP/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TEXGOYGW7DBS3N2QSSQONZ4ENIRQEAPG/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UQESRWMJCF4JEYJEAKLRM6CT55GLJAB7/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BUIP7T7Z4T3UHLXFWG6XIVDP4GYPD3AI/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/HVRDSJVZKMCXKKPP6PNR62T7RWZ3YSDZ/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2024q1/017430.html","tags":["Mailing List","Release Notes"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://nlnetlabs.nl/news/2024/Feb/13/unbound-1.19.1-released/","tags":["Release Notes"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20240307-0008/","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.isc.org/blogs/2024-bind-security-release/","tags":["Exploit","Mitigation","Press/Media Coverage"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2023-50868","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."}