{"id":"ALPINE-CVE-2021-3448","details":"A flaw was found in dnsmasq in versions before 2.85. When configured to use a specific server for a given network interface, dnsmasq uses a fixed port while forwarding queries. An attacker on the network, able to find the outgoing port used by dnsmasq, only needs to guess the random transmission ID to forge a reply and get it accepted by dnsmasq. This flaw makes a DNS Cache Poisoning attack much easier. The highest threat from this vulnerability is to data integrity.","modified":"2025-12-03T22:48:38.870993Z","published":"2021-04-08T23:15:12.597Z","upstream":["CVE-2021-3448"],"references":[{"type":"ADVISORY","url":"https://security.alpinelinux.org/vuln/CVE-2021-3448"}],"affected":[{"package":{"name":"dnsmasq","ecosystem":"Alpine:v3.10","purl":"pkg:apk/alpine/dnsmasq?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.85-r0"}]}],"versions":["2.46-r0","2.47-r0","2.49-r0","2.50-r0","2.50-r1","2.51-r0","2.52-r0","2.52-r1","2.55-r0","2.57-r0","2.58-r0","2.59-r0","2.59-r1","2.60-r0","2.61-r0","2.62-r0","2.63-r0","2.64-r0","2.65-r0","2.66-r0","2.66-r1","2.66-r2","2.67-r0","2.68-r0","2.69-r0","2.70-r0","2.71-r0","2.72-r0","2.72-r1","2.73-r0","2.75-r0","2.75-r1","2.75-r2","2.76-r0","2.76-r1","2.76-r2","2.76-r3","2.76-r4","2.77-r0","2.78-r0","2.78-r1","2.78-r2","2.79-r0","2.79-r1","2.79-r2","2.80-r0","2.80-r1","2.80-r2","2.80-r3","2.80-r4","2.83-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-3448.json"}},{"package":{"name":"dnsmasq","ecosystem":"Alpine:v3.11","purl":"pkg:apk/alpine/dnsmasq?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.85-r0"}]}],"versions":["2.46-r0","2.47-r0","2.49-r0","2.50-r0","2.50-r1","2.51-r0","2.52-r0","2.52-r1","2.55-r0","2.57-r0","2.58-r0","2.59-r0","2.59-r1","2.60-r0","2.61-r0","2.62-r0","2.63-r0","2.64-r0","2.65-r0","2.66-r0","2.66-r1","2.66-r2","2.67-r0","2.68-r0","2.69-r0","2.70-r0","2.71-r0","2.72-r0","2.72-r1","2.73-r0","2.75-r0","2.75-r1","2.75-r2","2.76-r0","2.76-r1","2.76-r2","2.76-r3","2.76-r4","2.77-r0","2.78-r0","2.78-r1","2.78-r2","2.79-r0","2.79-r1","2.79-r2","2.80-r0","2.80-r1","2.80-r2","2.80-r3","2.80-r4","2.80-r5","2.83-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-3448.json"}},{"package":{"name":"dnsmasq","ecosystem":"Alpine:v3.12","purl":"pkg:apk/alpine/dnsmasq?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.85-r0"}]}],"versions":["2.46-r0","2.47-r0","2.49-r0","2.50-r0","2.50-r1","2.51-r0","2.52-r0","2.52-r1","2.55-r0","2.57-r0","2.58-r0","2.59-r0","2.59-r1","2.60-r0","2.61-r0","2.62-r0","2.63-r0","2.64-r0","2.65-r0","2.66-r0","2.66-r1","2.66-r2","2.67-r0","2.68-r0","2.69-r0","2.70-r0","2.71-r0","2.72-r0","2.72-r1","2.73-r0","2.75-r0","2.75-r1","2.75-r2","2.76-r0","2.76-r1","2.76-r2","2.76-r3","2.76-r4","2.77-r0","2.78-r0","2.78-r1","2.78-r2","2.79-r0","2.79-r1","2.79-r2","2.80-r0","2.80-r1","2.80-r2","2.80-r3","2.80-r4","2.80-r5","2.81-r0","2.83-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-3448.json"}},{"package":{"name":"dnsmasq","ecosystem":"Alpine:v3.13","purl":"pkg:apk/alpine/dnsmasq?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.85-r0"}]}],"versions":["2.46-r0","2.47-r0","2.49-r0","2.50-r0","2.50-r1","2.51-r0","2.52-r0","2.52-r1","2.55-r0","2.57-r0","2.58-r0","2.59-r0","2.59-r1","2.60-r0","2.61-r0","2.62-r0","2.63-r0","2.64-r0","2.65-r0","2.66-r0","2.66-r1","2.66-r2","2.67-r0","2.68-r0","2.69-r0","2.70-r0","2.71-r0","2.72-r0","2.72-r1","2.73-r0","2.75-r0","2.75-r1","2.75-r2","2.76-r0","2.76-r1","2.76-r2","2.76-r3","2.76-r4","2.77-r0","2.78-r0","2.78-r1","2.78-r2","2.79-r0","2.79-r1","2.79-r2","2.80-r0","2.80-r1","2.80-r2","2.80-r3","2.80-r4","2.80-r5","2.81-r0","2.81-r1","2.82-r0","2.83-r0","2.84-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-3448.json"}},{"package":{"name":"dnsmasq","ecosystem":"Alpine:v3.14","purl":"pkg:apk/alpine/dnsmasq?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.85-r0"}]}],"versions":["2.46-r0","2.47-r0","2.49-r0","2.50-r0","2.50-r1","2.51-r0","2.52-r0","2.52-r1","2.55-r0","2.57-r0","2.58-r0","2.59-r0","2.59-r1","2.60-r0","2.61-r0","2.62-r0","2.63-r0","2.64-r0","2.65-r0","2.66-r0","2.66-r1","2.66-r2","2.67-r0","2.68-r0","2.69-r0","2.70-r0","2.71-r0","2.72-r0","2.72-r1","2.73-r0","2.75-r0","2.75-r1","2.75-r2","2.76-r0","2.76-r1","2.76-r2","2.76-r3","2.76-r4","2.77-r0","2.78-r0","2.78-r1","2.78-r2","2.79-r0","2.79-r1","2.79-r2","2.80-r0","2.80-r1","2.80-r2","2.80-r3","2.80-r4","2.80-r5","2.81-r0","2.81-r1","2.82-r0","2.83-r0","2.84-r0"],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-3448.json"}},{"package":{"name":"dnsmasq","ecosystem":"Alpine:v3.15","purl":"pkg:apk/alpine/dnsmasq?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.85-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-3448.json"}},{"package":{"name":"dnsmasq","ecosystem":"Alpine:v3.16","purl":"pkg:apk/alpine/dnsm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