{"id":"UBUNTU-CVE-2026-2291","details":"dnsmasqs extract_name() function can be abused to cause a heap buffer overflow, allowing an attacker to inject false DNS cache entries, which could result in DNS lookups to redirect to an attacker-controlled IP address, or to cause a DoS.","modified":"2026-05-20T16:11:37.242859613Z","published":"2026-05-11T12:00:00Z","related":["USN-8268-1"],"upstream":["CVE-2026-2291"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-2291"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-2291"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8268-1"}],"affected":[{"package":{"name":"dnsmasq","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/dnsmasq?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.68-1ubuntu0.2+esm5"}]}],"versions":["2.66-4ubuntu1","2.67-1","2.68-1","2.68-1ubuntu0.1","2.68-1ubuntu0.2","2.68-1ubuntu0.2+esm1","2.68-1ubuntu0.2+esm2","2.68-1ubuntu0.2+esm3"],"ecosystem_specific":{"binaries":[{"binary_version":"2.68-1ubuntu0.2+esm5","binary_name":"dnsmasq"},{"binary_name":"dnsmasq-base","binary_version":"2.68-1ubuntu0.2+esm5"},{"binary_version":"2.68-1ubuntu0.2+esm5","binary_name":"dnsmasq-utils"}],"availability":"Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-2291.json"}},{"package":{"name":"dnsmasq","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/dnsmasq?arch=source&distro=esm-infra%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.90-0ubuntu0.16.04.1+esm3"}]}],"versions":["2.75-1","2.75-1ubuntu0.16.04.1","2.75-1ubuntu0.16.04.2","2.75-1ubuntu0.16.04.3","2.75-1ubuntu0.16.04.4","2.75-1ubuntu0.16.04.5","2.75-1ubuntu0.16.04.7","2.75-1ubuntu0.16.04.8","2.75-1ubuntu0.16.04.10","2.75-1ubuntu0.16.04.10+esm1","2.79-1ubuntu0.16.04.1+esm1","2.79-1ubuntu0.16.04.1+esm2","2.90-0ubuntu0.16.04.1+esm1"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro","binaries":[{"binary_name":"dnsmasq","binary_version":"2.90-0ubuntu0.16.04.1+esm3"},{"binary_name":"dnsmasq-base","binary_version":"2.90-0ubuntu0.16.04.1+esm3"},{"binary_name":"dnsmasq-base-lua","binary_version":"2.90-0ubuntu0.16.04.1+esm3"},{"binary_name":"dnsmasq-utils","binary_version":"2.90-0ubuntu0.16.04.1+esm3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-2291.json"}},{"package":{"name":"dnsmasq","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/dnsmasq?arch=source&distro=esm-infra%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.90-0ubuntu0.18.04.1+esm3"}]}],"versions":["2.78-1","2.78-3","2.79-1","2.79-1ubuntu0.2","2.79-1ubuntu0.3","2.79-1ubuntu0.4","2.79-1ubuntu0.5","2.79-1ubuntu0.6","2.79-1ubuntu0.7","2.90-0ubuntu0.18.04.1+esm1"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro","binaries":[{"binary_name":"dnsmasq","binary_version":"2.90-0ubuntu0.18.04.1+esm3"},{"binary_name":"dnsmasq-base","binary_version":"2.90-0ubuntu0.18.04.1+esm3"},{"binary_version":"2.90-0ubuntu0.18.04.1+esm3","binary_name":"dnsmasq-base-lua"},{"binary_name":"dnsmasq-utils","binary_version":"2.90-0ubuntu0.18.04.1+esm3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-2291.json"}},{"package":{"name":"dnsmasq","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/dnsmasq?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.90-0ubuntu0.20.04.1+esm2"}]}],"versions":["2.80-1ubuntu2","2.80-1ubuntu4","2.80-1.1ubuntu1","2.80-1.1ubuntu1.2","2.80-1.1ubuntu1.3","2.80-1.1ubuntu1.4","2.80-1.1ubuntu1.5","2.80-1.1ubuntu1.6","2.80-1.1ubuntu1.7","2.90-0ubuntu0.20.04.1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.90-0ubuntu0.20.04.1+esm2","binary_name":"dnsmasq"},{"binary_name":"dnsmasq-base","binary_version":"2.90-0ubuntu0.20.04.1+esm2"},{"binary_name":"dnsmasq-base-lua","binary_version":"2.90-0ubuntu0.20.04.1+esm2"},{"binary_name":"dnsmasq-utils","binary_version":"2.90-0ubuntu0.20.04.1+esm2"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-2291.json"}},{"package":{"name":"dnsmasq","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/dnsmasq?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.90-0ubuntu0.22.04.3"}]}],"versions":["2.85-1ubuntu2","2.86-1.1","2.86-1.1ubuntu0.1","2.86-1.1ubuntu0.2","2.86-1.1ubuntu0.3","2.86-1.1ubuntu0.4","2.86-1.1ubuntu0.5","2.90-0ubuntu0.22.04.1"],"ecosystem_specific":{"binaries":[{"binary_name":"dnsmasq","binary_version":"2.90-0ubuntu0.22.04.3"},{"binary_name":"dnsmasq-base","binary_version":"2.90-0ubuntu0.22.04.3"},{"binary_version":"2.90-0ubuntu0.22.04.3","binary_name":"dnsmasq-base-lua"},{"binary_name":"dnsmasq-utils","binary_version":"2.90-0ubuntu0.22.04.3"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-2291.json"}},{"package":{"name":"dnsmasq","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/dnsmasq?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.90-2ubuntu0.3"}]}],"versions":["2.89-1","2.90-2","2.90-2build1","2.90-2build2","2.90-2ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.90-2ubuntu0.3","binary_name":"dnsmasq"},{"binary_version":"2.90-2ubuntu0.3","binary_name":"dnsmasq-base"},{"binary_name":"dnsmasq-base-lua","binary_version":"2.90-2ubuntu0.3"},{"binary_name":"dnsmasq-utils","binary_version":"2.90-2ubuntu0.3"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-2291.json"}},{"package":{"name":"dnsmasq","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/dnsmasq?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.91-1ubuntu0.2"}]}],"versions":["2.91-1","2.91-1build1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_version":"2.91-1ubuntu0.2","binary_name":"dnsmasq"},{"binary_name":"dnsmasq-base","binary_version":"2.91-1ubuntu0.2"},{"binary_version":"2.91-1ubuntu0.2","binary_name":"dnsmasq-base-lua"},{"binary_version":"2.91-1ubuntu0.2","binary_name":"dnsmasq-utils"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-2291.json"}},{"package":{"name":"dnsmasq","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/dnsmasq?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.92-1ubuntu0.2"}]}],"versions":["2.91-1build1","2.92~rc3-1","2.92-1"],"ecosystem_specific":{"binaries":[{"binary_name":"dnsmasq","binary_version":"2.92-1ubuntu0.2"},{"binary_version":"2.92-1ubuntu0.2","binary_name":"dnsmasq-base"},{"binary_version":"2.92-1ubuntu0.2","binary_name":"dnsmasq-base-lua"},{"binary_name":"dnsmasq-utils","binary_version":"2.92-1ubuntu0.2"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-2291.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L"},{"type":"Ubuntu","score":"medium"}]}