CVE-2024-0760: A flood of DNS messages over TCP may make the server unstable

CVE: CVE-2024-0760

Title: A flood of DNS messages over TCP may make the server unstable

Document version: 2.0

Posting date: 23 July 2024

Program impacted: BIND 9

Versions affected:

BIND

• 9.18.1 -> 9.18.27
• 9.19.0 -> 9.19.24

(Versions prior to 9.18.1 were not assessed.)

BIND Supported Preview Edition

• 9.18.11-S1 -> 9.18.27-S1

(Versions prior to 9.18.24-S1 were not assessed.)

Severity: High

Exploitable: Remotely

Description:

A malicious client can send many DNS messages over TCP, potentially causing the server to become unstable while the attack is in progress. The server may recover after the attack ceases. Use of ACLs will not mitigate the attack.

Impact:

The server can become unresponsive until sometime after the attack ends.

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:

No workarounds known.

Active exploits:

This flaw was discovered in internal testing. We are not aware of any active exploits.

Solution:

Upgrade to the patched release most closely related to your current version of BIND 9:

• 9.18.28
• 9.20.0

BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers.

• 9.18.28-S1

Document revision history:

• 1.0 Early Notification, 10 July 2024
• 1.1 Revised public disclosure date, 16 July 2024
• 2.0 Public disclosure, 23 July 2024

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-2024-0760 is the complete and official security advisory document.

Legal Disclaimer:

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