{"id":"CVE-2026-93008","state":"PUBLISHED","title":"Dnsmasq: dnsmasq: out-of-bailiwick cache injection through cname chase in split-dns configurations","description":"A flaw was found in dnsmasq. When following a CNAME in a DNS response, the resolver can cache records for the CNAME target without checking that those records belong to the responding server's authorized zone. In split-DNS deployments that send some domains to a specific upstream, an attacker who controls that upstream can inject cache entries for unrelated names. 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Do not point server=/domain/ at untrusted or attacker-reachable DNS servers.\n2. Restrict dnsmasq to communicate only with trusted upstream resolvers at the firewall.\n3. For local=/domain/ zones, define all names that should be served locally.\n4. Do not rely on --dnssec to mitigate this for unsigned zones. Insecure records are still cached."}],"timeline":[{"lang":"en","time":"2026-09-14T00:00:00.000Z","value":"Reported to Red Hat."},{"lang":"en","time":"2026-10-28T09:32:00.000Z","value":"Made public."}],"credits":[{"lang":"en","value":"Red Hat would like to thank Shubham Raj (Causal Security) for reporting this issue."}],"x_generator":{"engine":"cvelib 1.8.0"}}}}}