{"schemaVersion":3,"id":"CVE-2026-27854","aliases":["UBUNTU-CVE-2026-27854","DEBIAN-CVE-2026-27854"],"status":"published","duplicateOf":null,"title":null,"description":"An attacker might be able to trigger a use-after-free by sending crafted DNS queries to a DNSdist using the DNSQuestion:getEDNSOptions method in custom Lua code. 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At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory \"belongs\" to the code that operates on the new pointer.","type":"weakness","status":"Stable","abstraction":"Variant","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/416.html"}],"affected":[{"vendor":"debian","product":"dnsdist","name":"dnsdist","label":"dnsdist","ecosystem":"Debian","cpePart":null,"purl":"pkg:deb/debian/dnsdist","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null},{"text":"< 1.9.14-0+deb13u1","noFixRecorded":false,"fixedIn":null},{"text":"< 2.0.3-1","noFixRecorded":false,"fixedIn":null}],"versionsText":"All versions (No fix recorded) | < 1.9.14-0+deb13u1 | < 2.0.3-1","eol":null,"hubHref":null},{"vendor":"ubuntu","product":"dnsdist","name":"dnsdist","label":"dnsdist","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/dnsdist","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null},{"vendor":"powerdns","product":"dnsdist","name":"dnsdist","label":"dnsdist","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ 1.9.0, < 1.9.12","noFixRecorded":false,"fixedIn":null},{"text":"≥ 2.0.0, < 2.0.3","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ 1.9.0, < 1.9.12 | ≥ 2.0.0, < 2.0.3","eol":null,"hubHref":"/vendor/powerdns/dnsdist"}],"affectedCount":3,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-02.html","label":"www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-02.html","hostname":"www.dnsdist.org","tags":["REPORT","Vendor Advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-27854","label":"ubuntu.com/security/CVE-2026-27854","hostname":"ubuntu.com","tags":["REPORT"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-27854","label":"www.cve.org/CVERecord?id=CVE-2026-27854","hostname":"www.cve.org","tags":["REPORT"]},{"url":"https://downloads.powerdns.com/patches/2026-02/","label":"downloads.powerdns.com/patches/2026-02/","hostname":"downloads.powerdns.com","tags":["REPORT"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-27854","label":"security-tracker.debian.org/tracker/CVE-2026-27854","hostname":"security-tracker.debian.org","tags":["Advisory"]}],"lineage":{"upstream":[],"downstream":["OPENSUSE-SU-2026:10473-1","OPENSUSE-SU-2026:21015-1","SUSE-SU-2026:1618-1","SUSE-SU-2026:22319-1"],"duplicates":[],"related":["OPENSUSE-SU-2026:10473-1","OPENSUSE-SU-2026:21015-1","SUSE-SU-2026:1618-1","SUSE-SU-2026:22319-1"]},"timeline":[{"kind":"published","date":"2026-03-31T12:06:46.648Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-04-02T13:46:22.087Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":30,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-20T06:57:02.783Z","stale":false,"partial":false}}