{"id":"CVE-2020-25686","state":"PUBLISHED","title":"A flaw was found in dnsmasq before version 2.83. When receiving a query, dnsmasq does not check for an existing pending request for the same name and forwards a new request. By def","description":"A flaw was found in dnsmasq before version 2.83. When receiving a query, dnsmasq does not check for an existing pending request for the same name and forwards a new request. By default, a maximum of 150 pending queries can be sent to upstream servers, so there can be at most 150 queries for the same name. This flaw allows an off-path attacker on the network to substantially reduce the number of attempts that it would have to perform to forge a reply and have it accepted by dnsmasq. This issue is mentioned in the \"Birthday Attacks\" section of RFC5452. If chained with CVE-2020-25684, the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity.","publishedAt":"2021-01-20T16:47:17.000Z","updatedAt":"2025-11-04T19:12:14.331Z","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=1890125","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://www.arista.com/en/support/advisories-notices/security-advisories/12135-security-advisory-61","https://www.kb.cert.org/vuls/id/434904"],"weaknesses":["CWE-358"],"ingestedAt":"2026-10-29T19:47:05.429Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2020/25xxx/CVE-2020-25686.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2020-25686","state":"PUBLISHED","datePublished":"2021-01-20T16:47:17.000Z","dateUpdated":"2025-11-04T19:12:14.331Z","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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