CVE: CVE-2026-3119
Title: Authenticated query containing a TKEY record may cause named to terminate unexpectedly
Document version: 2.0
Posting date: 25 March 2026
Program impacted: BIND 9
Versions affected:
BIND
- 9.20.0 -> 9.20.20
- 9.21.0 -> 9.21.19
BIND Supported Preview Edition
- 9.20.9-S1 -> 9.20.20-S1
Versions NOT affected:
BIND
- 9.18.0 -> 9.18.46
BIND Supported Preview Edition
- 9.18.11-S1 -> 9.18.46-S1
Severity: Medium
Exploitable: Remotely
Description:
Under certain conditions, named may crash when processing a correctly signed query containing a TKEY record. The affected code can only be reached if an incoming request has a valid transaction signature (TSIG) from a key declared in the named configuration.
Impact:
If this situation is encountered, named will terminate unexpectedly.
-
Authoritative servers are affected by this vulnerability.
-
Resolvers are affected by this vulnerability.
CVSS Score: 6.5
CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit: https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H&version=3.1.
Workarounds:
Remove any TSIG keys that might be used by an attacker.
Active exploits:
We are not aware of any active exploits.
Solution:
Upgrade to the patched release most closely related to your current version of BIND 9:
- 9.20.21
- 9.21.20
BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers.
- 9.20.21-S1
Acknowledgments:
ISC would like to thank Vitaly Simonovich for bringing this vulnerability to our attention.
Document revision history:
- 1.0 Early Notification, 18 March 2026
- 2.0 Public disclosure, 25 March 2026
Related documents:
See our BIND 9 Security Vulnerability Matrix for a complete listing of security vulnerabilities and versions affected.
Do you still have questions? Questions regarding this advisory should be mailed to bind-security@isc.org or posted as confidential GitLab issues at https://gitlab.isc.org/isc-projects/bind9/-/issues/new?issue[confidential]=true.
Note:
ISC patches only currently supported versions. When possible we indicate EOL versions affected. For current information on which versions are actively supported, please see https://www.isc.org/download/.
ISC Security Vulnerability Disclosure Policy:
Details of our current security advisory policy and practice can be found in the ISC Software Defect and Security Vulnerability Disclosure Policy at https://kb.isc.org/docs/aa-00861.
The Knowledgebase article https://kb.isc.org/docs/cve-2026-3119 is the complete and official security advisory document.
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