{"schemaVersion":3,"id":"CVE-2020-25684","aliases":["ALPINE-CVE-2020-25684","UBUNTU-CVE-2020-25684","DEBIAN-CVE-2020-25684"],"status":"published","duplicateOf":null,"title":null,"description":"A flaw was found in dnsmasq before version 2.83. When getting a reply from a forwarded query, dnsmasq checks in the forward.c:reply_query() if the reply destination address/port is used by the pending forwarded queries. However, it does not use the address/port to retrieve the exact forwarded query, substantially reducing the number of attempts an attacker on the network would have to perform to forge a reply and get it accepted by dnsmasq. This issue contrasts with RFC5452, which specifies a query's attributes that all must be used to match a reply. This flaw allows an attacker to perform a DNS Cache Poisoning attack. If chained with CVE-2020-25685 or CVE-2020-25686, the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity.","dates":{"published":"2021-01-20T15:22:21.000Z","modified":"2025-11-04T19:12:12.109Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":4.3,"severity":"medium","version":"2.0","versionLabel":"v2.0","source":"NVD","vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"OSV · Alpine","score":3.7,"severity":"low","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","exploitability":5.6,"impact":2.3,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Ubuntu","score":3.7,"severity":"low","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","exploitability":5.6,"impact":2.3,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Debian","score":3.7,"severity":"low","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","exploitability":5.6,"impact":2.3,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":3.7,"severity":"low","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":4.3,"severity":"medium","vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.04075,"percentile":0.9058,"severity":"low","asOf":"2026-10-19T00:00:00.000Z","change":{"pp":0.034,"baselineDate":"2026-09-19T00:00:00.000Z","baselineScore":0.04041},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.04075,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.04075,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.04075,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.04075,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.04075,"percentile":0.9058}],"last30":[{"date":"2026-09-19T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.04041,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.04075,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.04075,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.04075,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.04075,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.04075,"percentile":0.9058}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-358","name":"Improperly Implemented Security Check for Standard","description":"The product does not implement or incorrectly implements one or more security-relevant checks as specified by the design of a standardized algorithm, protocol, or technique.","type":"weakness","status":"Draft","abstraction":"Base","likelihoodOfExploit":null,"url":"https://cwe.mitre.org/data/definitions/358.html"}],"affected":[{"vendor":"alpine","product":"dnsmasq","name":"dnsmasq","label":"dnsmasq","ecosystem":"Alpine Linux","cpePart":null,"purl":"pkg:apk/alpine/dnsmasq","purlType":"apk","versions":[{"text":"< 2.83-r0","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 2.83-r0","eol":null,"hubHref":null},{"vendor":"arista","product":"eos","name":"eos","label":"eos","ecosystem":null,"cpePart":"o","purl":null,"purlType":null,"versions":[{"text":"≥ 4.21, < 4.21.14m","noFixRecorded":false,"fixedIn":null},{"text":"≥ 4.22, < 4.22.9m","noFixRecorded":false,"fixedIn":null},{"text":"≥ 4.23, < 4.23.7m","noFixRecorded":false,"fixedIn":null},{"text":"≥ 4.24, < 4.24.5m","noFixRecorded":false,"fixedIn":null},{"text":"≥ 4.25, < 4.25.2f","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ 4.21, < 4.21.14m | ≥ 4.22, < 4.22.9m | ≥ 4.23, < 4.23.7m | ≥ 4.24, < 4.24.5m | ≥ 4.25, < 4.25.2f","eol":null,"hubHref":"/vendor/arista/eos"},{"vendor":"debian","product":"dnsmasq","name":"dnsmasq","label":"dnsmasq","ecosystem":"Debian","cpePart":null,"purl":"pkg:deb/debian/dnsmasq","purlType":"deb","versions":[{"text":"< 2.83-1","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 2.83-1","eol":null,"hubHref":null},{"vendor":"ubuntu","product":"dnsmasq","name":"dnsmasq","label":"dnsmasq","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/dnsmasq","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null},{"text":"< 2.75-1ubuntu0.16.04.7","noFixRecorded":false,"fixedIn":null},{"text":"< 2.79-1ubuntu0.2","noFixRecorded":false,"fixedIn":null},{"text":"< 2.80-1.1ubuntu1.2","noFixRecorded":false,"fixedIn":null}],"versionsText":"All versions (No fix recorded) | < 2.75-1ubuntu0.16.04.7 | < 2.79-1ubuntu0.2 | < 2.80-1.1ubuntu1.2","eol":null,"hubHref":null},{"vendor":"debian","product":"debian_linux","name":"debian linux","label":"debian_linux","ecosystem":null,"cpePart":"o","purl":null,"purlType":null,"versions":[{"text":"9.0","noFixRecorded":false,"fixedIn":null},{"text":"10.0","noFixRecorded":false,"fixedIn":null}],"versionsText":"9.0 | 10.0","eol":{"isEol":true,"eolDate":"2022-07-01T00:00:00.000Z","matchMethod":"cpe","cycle":{"name":"9","label":"9 (Stretch)","eolFrom":"2022-07-01T00:00:00.000Z","isLts":false,"isMaintained":true,"latestVersion":"9.13"},"product":{"name":"debian","label":"Debian","category":"os"}},"hubHref":"/vendor/debian/debian_linux"},{"vendor":"fedoraproject","product":"fedora","name":"fedora","label":"fedora","ecosystem":null,"cpePart":"o","purl":null,"purlType":null,"versions":[{"text":"32","noFixRecorded":false,"fixedIn":null},{"text":"33","noFixRecorded":false,"fixedIn":null}],"versionsText":"32 | 33","eol":{"isEol":true,"eolDate":"2021-05-25T00:00:00.000Z","matchMethod":"cpe","cycle":{"name":"32","label":"32","eolFrom":"2021-05-25T00:00:00.000Z","isLts":false,"isMaintained":false,"latestVersion":null},"product":{"name":"fedora","label":"Fedora Linux","category":"os"}},"hubHref":"/vendor/fedoraproject/fedora"},{"vendor":"thekelleys","product":"dnsmasq","name":"dnsmasq","label":"dnsmasq","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 2.83","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 2.83","eol":null,"hubHref":"/vendor/thekelleys/dnsmasq"}],"affectedCount":7,"eol":{"hasEol":true,"count":2},"references":[{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1889686","label":"bugzilla.redhat.com/show_bug.cgi?id=1889686","hostname":"bugzilla.redhat.com","tags":["X Refsource MISC","Issue Tracking","Patch","Third Party Advisory"]},{"url":"https://www.jsof-tech.com/disclosures/dnspooq/","label":"www.jsof-tech.com/disclosures/dnspooq/","hostname":"www.jsof-tech.com","tags":["X Refsource MISC","REPORT","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WYW3IR6APUSKOYKL5FT3ACTIHWHGQY32/","label":"lists.fedoraproject.org/archives/…","hostname":"lists.fedoraproject.org","tags":["Vendor Advisory","X Refsource FEDORA"]},{"url":"https://security.gentoo.org/glsa/202101-17","label":"security.gentoo.org/glsa/202101-17","hostname":"security.gentoo.org","tags":["Vendor Advisory","X Refsource GENTOO","Third Party Advisory"]},{"url":"https://www.debian.org/security/2021/dsa-4844","label":"www.debian.org/security/2021/dsa-4844","hostname":"www.debian.org","tags":["Vendor Advisory","X Refsource DEBIAN","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGB7HL3OWHTLEPSMLDGOMXQKG3KM2QME/","label":"lists.fedoraproject.org/archives/…","hostname":"lists.fedoraproject.org","tags":["Vendor Advisory","X Refsource FEDORA"]},{"url":"https://lists.debian.org/debian-lts-announce/2021/03/msg00027.html","label":"lists.debian.org/debian-lts-announce/2021/03/msg00027.html","hostname":"lists.debian.org","tags":["Mailing List","X Refsource MLIST","Third Party Advisory"]},{"url":"https://www.arista.com/en/support/advisories-notices/security-advisories/12135-security-advisory-61","label":"www.arista.com/en/support/advisories-notices/security-advisories/12135-security-advisory-61","hostname":"www.arista.com","tags":["X Refsource MISC","Third Party Advisory"]},{"url":"https://www.kb.cert.org/vuls/id/434904","label":"www.kb.cert.org/vuls/id/434904","hostname":"www.kb.cert.org","tags":[]},{"url":"https://security.alpinelinux.org/vuln/CVE-2020-25684","label":"security.alpinelinux.org/vuln/CVE-2020-25684","hostname":"security.alpinelinux.org","tags":["Advisory"]},{"url":"https://ubuntu.com/security/CVE-2020-25684","label":"ubuntu.com/security/CVE-2020-25684","hostname":"ubuntu.com","tags":["REPORT"]},{"url":"http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2021q1/014599.html","label":"lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2021q1/014599.html","hostname":"lists.thekelleys.org.uk","tags":["REPORT"]},{"url":"https://ubuntu.com/security/notices/USN-4698-1","label":"ubuntu.com/security/notices/USN-4698-1","hostname":"ubuntu.com","tags":["Advisory"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-25684","label":"www.cve.org/CVERecord?id=CVE-2020-25684","hostname":"www.cve.org","tags":["REPORT"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2020-25684","label":"security-tracker.debian.org/tracker/CVE-2020-25684","hostname":"security-tracker.debian.org","tags":["Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-25684","label":"nvd.nist.gov/vuln/detail/CVE-2020-25684","hostname":"nvd.nist.gov","tags":["Oval","Advisory"]}],"lineage":{"upstream":[],"downstream":["DLA-2604-1","DSA-4844-1","MGASA-2021-0059","OPENSUSE-SU-2021:0124-1","OPENSUSE-SU-2021:0129-1","OPENSUSE-SU-2024:10721-1","RHSA-2021:0150","RHSA-2021:0151","RHSA-2021:0152","RHSA-2021:0153","RHSA-2021:0154","RHSA-2021:0155","RHSA-2021:0156","RHSA-2021:0240","RHSA-2021:0245","RHSA-2021:0395","RHSA-2021:0401","SUSE-SU-2021:0162-1","SUSE-SU-2021:0163-1","SUSE-SU-2021:0166-1","SUSE-SU-2021:14603-1","SUSE-SU-2021:14604-1","USN-4698-1"],"duplicates":[],"related":["OPENSUSE-SU-2021:0124-1","OPENSUSE-SU-2021:0129-1","OPENSUSE-SU-2024:10721-1","SUSE-SU-2021:0162-1","SUSE-SU-2021:0163-1","SUSE-SU-2021:0166-1","SUSE-SU-2021:14603-1","SUSE-SU-2021:14604-1","USN-4698-1"]},"timeline":[{"kind":"published","date":"2021-01-20T15:22:21.000Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2025-11-04T19:12:12.109Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":18,"level":"low","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-19T19:11:34.516Z","stale":false,"partial":false}}