CVE-2023-5517: Querying RFC 1918 reverse zones may cause an assertion failure when "nxdomain-redirect" is enabled

Published Feb 12, 2024
·
Updated

A flaw in query-handling code can cause named to exit prematurely with an assertion failure when:

- nxdomain-redirect <domain>; is configured, and - the resolver receives a PTR query for an RFC 1918 address that would normally result in an authoritative NXDOMAIN response. This issue affects BIND 9 versions 9.12.0 through 9.16.45, 9.18.0 through 9.18.21, 9.19.0 through 9.19.19, 9.16.8-S1 through 9.16.45-S1, and 9.18.11-S1 through 9.18.21-S1.

Other sources

A flaw in query-handling code can cause named to exit prematurely with an assertion failure when:

- nxdomain-redirect <domain>; is configured, and - the resolver receives a PTR query for an RFC 1918 address that would normally result in an authoritative NXDOMAIN response.

Red Hat

Affected Software

23 affected componentsFixes available
redhat/bind<9.16.48
9.16.48
redhat/bind<9.18.24
9.18.24
redhat/bind<9.19.21
9.19.21
NetApp Active Iq Unified Manager Vmware Vsphere
Fedoraproject Fedora=38
Fedoraproject Fedora=39
ISC BIND>=9.12.0<=9.16.45
ISC BIND>=9.18.0<=9.18.21
ISC BIND>=9.19.0<=9.19.19
ISC BIND=9.16.8-s1
ISC BIND=9.16.11-s1
ISC BIND=9.16.12-s1
ISC BIND=9.16.13-s1
ISC BIND=9.16.14-s1
ISC BIND=9.16.21-s1
ISC BIND=9.16.32-s1
ISC BIND=9.16.36-s1
ISC BIND=9.16.43-s1
ISC BIND=9.16.45-s1
ISC BIND=9.18.11-s1
ISC BIND=9.18.18-s1
ISC BIND=9.18.21-s1
debian/bind9
1:9.16.50-1~deb11u21:9.16.50-1~deb11u31:9.18.33-1~deb12u21:9.20.8-6

Remediation

Information

Upgrade to the patched release most closely related to your current version of BIND 9: 9.16.48, 9.18.24, 9.19.21, 9.16.48-S1, or 9.18.24-S1.

Event History

Feb 13, 2024
CVE Published
via MITRE·02:04 PM
Data Sourced
via MITRE·02:04 PM
RemedyDescriptionSeverity
May 31, 2024
Data Sourced
via Launchpad·05:49 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·06:04 PM
RemedyDescriptionSeverityAffected Software
Apr 29, 2025
Data Sourced
via Debian·05:38 AM
DescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2023-5517?

CVE-2023-5517 has a high severity rating due to the potential for causing named to exit prematurely.

2

How do I fix CVE-2023-5517?

To fix CVE-2023-5517, upgrade to bind version 9.16.48, 9.18.24, or 9.19.21 or later.

3

What systems are affected by CVE-2023-5517?

CVE-2023-5517 affects various versions of ISC BIND, Red Hat bind, and Debian bind9 installations.

4

What scenarios trigger CVE-2023-5517?

CVE-2023-5517 is triggered when nxdomain-redirect is configured alongside a PTR query for an RFC 1918 address.

5

How can I identify if my system is vulnerable to CVE-2023-5517?

You can identify vulnerability to CVE-2023-5517 by checking if you are running an affected version of bind.

Contact

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