{"id":"CVE-2020-25683","state":"PUBLISHED","title":"A flaw was found in dnsmasq before version 2.83. A heap-based buffer overflow was discovered in dnsmasq when DNSSEC is enabled and before it validates the received DNS entries. A r","description":"A flaw was found in dnsmasq before version 2.83. A heap-based buffer overflow was discovered in dnsmasq when DNSSEC is enabled and before it validates the received DNS entries. A remote attacker, who can create valid DNS replies, could use this flaw to cause an overflow in a heap-allocated memory. This flaw is caused by the lack of length checks in rfc1035.c:extract_name(), which could be abused to make the code execute memcpy() with a negative size in get_rdata() and cause a crash in dnsmasq, resulting in a denial of service. The highest threat from this vulnerability is to system availability.","publishedAt":"2021-01-20T15:25:04.000Z","updatedAt":"2025-11-04T19:12:11.018Z","severity":null,"assigner":"redhat","products":["n/a dnsmasq"],"affected":[{"vendor":"n/a","product":"dnsmasq","versions":[{"version":"dnsmasq 2.83","status":"affected"}]}],"references":["https://www.jsof-tech.com/disclosures/dnspooq/","https://bugzilla.redhat.com/show_bug.cgi?id=1882018","https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WYW3IR6APUSKOYKL5FT3ACTIHWHGQY32/","https://security.gentoo.org/glsa/202101-17","https://www.debian.org/security/2021/dsa-4844","https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGB7HL3OWHTLEPSMLDGOMXQKG3KM2QME/","https://lists.debian.org/debian-lts-announce/2021/03/msg00027.html","https://www.kb.cert.org/vuls/id/434904"],"weaknesses":["CWE-122"],"ingestedAt":"2026-10-29T19:47:05.429Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2020/25xxx/CVE-2020-25683.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2020-25683","state":"PUBLISHED","datePublished":"2021-01-20T15:25:04.000Z","dateUpdated":"2025-11-04T19:12:11.018Z","assignerShortName":"redhat","assignerOrgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","dateReserved":"2020-09-16T00:00:00.000Z"},"containers":{"cna":{"descriptions":[{"lang":"en","value":"A flaw was found in dnsmasq before version 2.83. 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