{"id":"CVE-2026-19033","title":"For a secondary zone with transfers restricted by TSIG, `named` may start to serve the data provided in a zone transfer before the final message with the TSIG signature arrives","summary":"For a secondary zone with transfers restricted by TSIG, `named` may start to serve the data provided in a zone transfer before the final message with the TSIG signature arrives. This could allow an attacker that does not actually possess…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L","cwe":["CWE-349","CWE-347"],"vendor":"ISC","product":"BIND 9","affected":["bind_9 >= 9.11.0 <= 9.18.50","bind_9 >= 9.20.0 <= 9.20.27","bind_9 >= 9.21.0 <= 9.21.25","bind_9 >= 9.11.3-S1 <= 9.18.50-S1","bind_9 >= 9.20.9-S1 <= 9.20.27-S1"],"published":"2026-09-16","updated":"2026-09-17","sourceUpdated":"2026-09-17T18:16:38.860","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-19033","references":[{"url":"https://downloads.isc.org/isc/bind9/9.20.29","label":"security-officer@isc.org"},{"url":"https://downloads.isc.org/isc/bind9/9.21.26","label":"security-officer@isc.org"},{"url":"https://kb.isc.org/docs/cve-2026-19033","label":"security-officer@isc.org"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-19033.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-19033"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2535479"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-19033"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-19033"},{"url":"https://access.redhat.com/errata/RHSA-2026:68279"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-17T17:36:40.215995Z"},"ingestedAt":"2026-09-16T14:57:28.063Z","epss":0.00203,"epssPercentile":0.10546,"patched":["hardened_images"],"slug":"CVE-2026-19033","body":"## Overview\n\nFor a secondary zone with transfers restricted by TSIG, `named` may start to serve the data provided in a zone transfer before the final message with the TSIG signature arrives. This could allow an attacker that does not actually possess a valid TSIG signature to send unauthorized zone contents to a secondary server. Although no TSIG signature ever arrives, `named` does not rollback to the pre-transfer state. To exploit the vulnerability, the transfer must be a multi-message TCP IXFR, as described by RFC 8945.\nThis issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, … · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-19033.json)\n- **RHSA-2026:68279** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68279)","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}