{"id":"UBUNTU-CVE-2023-4236","details":"A flaw in the networking code handling DNS-over-TLS queries may cause `named` to terminate unexpectedly due to an assertion failure. This happens when internal data structures are incorrectly reused under significant DNS-over-TLS query load. This issue affects BIND 9 versions 9.18.0 through 9.18.18 and 9.18.11-S1 through 9.18.18-S1.","modified":"2026-04-22T14:13:15.116713Z","published":"2023-09-20T00:00:00Z","related":["USN-6390-1"],"upstream":["CVE-2023-4236"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2023-4236"},{"type":"REPORT","url":"https://kb.isc.org/docs/cve-2023-4236"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-6390-1"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2023-4236"}],"affected":[{"package":{"name":"bind9","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/bind9@1:9.18.12-0ubuntu0.22.04.3?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:9.18.12-0ubuntu0.22.04.3"}]}],"versions":["1:9.16.15-1ubuntu1","1:9.16.15-1ubuntu2","1:9.16.15-1ubuntu3","1:9.18.0-2ubuntu1","1:9.18.0-2ubuntu2","1:9.18.0-2ubuntu3","1:9.18.1-1ubuntu1","1:9.18.1-1ubuntu1.1","1:9.18.1-1ubuntu1.2","1:9.18.1-1ubuntu1.3","1:9.18.12-0ubuntu0.22.04.1","1:9.18.12-0ubuntu0.22.04.2"],"ecosystem_specific":{"binaries":[{"binary_version":"1:9.18.12-0ubuntu0.22.04.3","binary_name":"bind9"},{"binary_version":"1:9.18.12-0ubuntu0.22.04.3","binary_name":"bind9-dnsutils"},{"binary_name":"bind9-host","binary_version":"1:9.18.12-0ubuntu0.22.04.3"},{"binary_name":"bind9-libs","binary_version":"1:9.18.12-0ubuntu0.22.04.3"},{"binary_version":"1:9.18.12-0ubuntu0.22.04.3","binary_name":"bind9-utils"},{"binary_name":"bind9utils","binary_version":"1:9.18.12-0ubuntu0.22.04.3"},{"binary_name":"dnsutils","binary_version":"1:9.18.12-0ubuntu0.22.04.3"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-4236.json"}},{"package":{"name":"bind9","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/bind9@1:9.18.18-0ubuntu2?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:9.18.18-0ubuntu2"}]}],"ecosystem_specific":{"binaries":[{"binary_name":"bind9","binary_version":"1:9.18.18-0ubuntu2"},{"binary_name":"bind9-dnsutils","binary_version":"1:9.18.18-0ubuntu2"},{"binary_name":"bind9-host","binary_version":"1:9.18.18-0ubuntu2"},{"binary_name":"bind9-libs","binary_version":"1:9.18.18-0ubuntu2"},{"binary_name":"bind9-utils","binary_version":"1:9.18.18-0ubuntu2"},{"binary_name":"bind9utils","binary_version":"1:9.18.18-0ubuntu2"},{"binary_name":"dnsutils","binary_version":"1:9.18.18-0ubuntu2"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-4236.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:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}