CVE: CVE-2024-11187
Title: Many records in the additional section cause CPU exhaustion
Document version: 2.0
Posting date: 29 January 2025
Program impacted: BIND 9
Versions affected:
BIND
- 9.11.0 -> 9.11.37
- 9.16.0 -> 9.16.50
- 9.18.0 -> 9.18.32
- 9.20.0 -> 9.20.4
- 9.21.0 -> 9.21.3
(Versions prior to 9.11.37 were not assessed.)
BIND Supported Preview Edition
- 9.11.3-S1 -> 9.11.37-S1
- 9.16.8-S1 -> 9.16.50-S1
- 9.18.11-S1 -> 9.18.32-S1
(Versions prior to 9.11.37-S1 were not assessed.)
Severity: High
Exploitable: Remotely
Description:
It is possible to construct a zone such that some queries to it will generate responses containing numerous records in the Additional section. An attacker sending many such queries can cause either the authoritative server itself or an independent resolver to use disproportionate resources processing the queries. Zones will usually need to have been deliberately crafted to attack this exposure.
Impact:
A named instance vulnerable to this issue can be compelled to consume excessive CPU resources up to the point where exhaustion of resources effectively prevents the server from responding to other client queries. This issue is most likely to affect resolvers but could also degrade authoritative server performance.
-
Authoritative servers are affected by this vulnerability.
-
Resolvers are affected by this vulnerability.
CVSS Score: 7.5
CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/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:N/UI:N/S:U/C:N/I:N/A:H&version=3.1.
Workarounds:
Setting option minimal-responses yes; provides an effective workaround.
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:
- 9.18.33
- 9.20.5
- 9.21.4
BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers.
- 9.18.33-S1
Acknowledgments:
ISC would like to thank Toshifumi Sakaguchi for bringing this vulnerability to our attention.
Document revision history:
- 1.0 Early Notification, 22 January 2025
- 2.0 Public disclosure, 29 January 2025
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-2024-11187 is the complete and official security advisory document.
Legal Disclaimer:
Internet Systems Consortium (ISC) is providing this notice on an "AS IS" basis. No warranty or guarantee of any kind is expressed in this notice and none should be implied. ISC expressly excludes and disclaims any warranties regarding this notice or materials referred to in this notice, including, without limitation, any implied warranty of merchantability, fitness for a particular purpose, absence of hidden defects, or of non-infringement. Your use or reliance on this notice or materials referred to in this notice is at your own risk. ISC may change this notice at any time. A stand-alone copy or paraphrase of the text of this document that omits the document URL is an uncontrolled copy. Uncontrolled copies may lack important information, be out of date, or contain factual errors.