{"id":"CVE-2021-25219","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-25219","generatedAt":"2026-10-27T20:19:20.519Z","title":"In BIND 9.3.0 -> 9.11.35, 9.12.0 -> 9.16.21, and versions 9.9.3-S1 -> 9.11.35-S1 and 9.16.8-S1 -> 9.16.21-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.18 of the BIND 9.17 development branch, exploitation of broken…","description":"In BIND 9.3.0 -> 9.11.35, 9.12.0 -> 9.16.21, and versions 9.9.3-S1 -> 9.11.35-S1 and 9.16.8-S1 -> 9.16.21-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.18 of the BIND 9.17 development branch, exploitation of broken authoritative servers using a flaw in response processing can cause degradation in BIND resolver performance. The way the lame cache is currently designed makes it possible for its internal data structures to grow almost infinitely, which may cause significant delays in client query processing.","published":"2021-10-27T21:15:08.000Z","lastModified":"2026-06-17T03:41:40.000Z","status":"Modified","sourceIdentifier":"security-officer@isc.org","cvss":{"version":"3.1","score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"cwe":[],"affected":["isc/bind","debian/debian linux","fedoraproject/fedora","netapp/h300s firmware","netapp/h500s firmware","netapp/h700s firmware","netapp/h300e firmware","netapp/h500e firmware","netapp/h700e firmware","netapp/h410s firmware","netapp/h410c firmware","netapp/cloud backup","siemens/sinec infrastructure network services","oracle/http server","oracle/zfs storage appliance kit"],"epss":{"score":0.10951,"percentile":0.95856,"date":"2026-10-26","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 11.0%, higher than 96% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf","tags":["Patch","Third Party Advisory"],"source":"security-officer@isc.org"},{"url":"https://kb.isc.org/v1/docs/cve-2021-25219","tags":["Vendor Advisory"],"source":"security-officer@isc.org"},{"url":"https://lists.debian.org/debian-lts-announce/2021/11/msg00001.html","tags":["Mailing List","Third Party Advisory"],"source":"security-officer@isc.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EF4NAVRV4H3W4GA3LGGZYUKD3HSJBAVW/","source":"security-officer@isc.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YGV7SA27CTYLGFJSPUM3V36ZWK7WWDI4/","source":"security-officer@isc.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YTKC4E3HUOLYN5IA4EBL4VAQSWG2ZVTX/","source":"security-officer@isc.org"},{"url":"https://security.gentoo.org/glsa/202210-25","tags":["Third Party Advisory"],"source":"security-officer@isc.org"},{"url":"https://security.netapp.com/advisory/ntap-20211118-0002/","tags":["Third Party Advisory"],"source":"security-officer@isc.org"},{"url":"https://www.debian.org/security/2021/dsa-4994","tags":["Third Party Advisory"],"source":"security-officer@isc.org"},{"url":"https://www.oracle.com/security-alerts/cpuapr2022.html","tags":["Third Party Advisory"],"source":"security-officer@isc.org"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://kb.isc.org/v1/docs/cve-2021-25219","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2021/11/msg00001.html","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EF4NAVRV4H3W4GA3LGGZYUKD3HSJBAVW/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YGV7SA27CTYLGFJSPUM3V36ZWK7WWDI4/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YTKC4E3HUOLYN5IA4EBL4VAQSWG2ZVTX/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202210-25","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20211118-0002/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2021/dsa-4994","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com/security-alerts/cpuapr2022.html","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-25219","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."}