CVE-2023-5517

Publication date 13 February 2024

Last updated 4 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

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.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
bind9	25.04 plucky	Fixed 1:9.18.24-0ubuntu1
	24.10 oracular	Fixed 1:9.18.24-0ubuntu1
	24.04 LTS noble	Fixed 1:9.18.24-0ubuntu1
	23.10 mantic	Fixed 1:9.18.18-0ubuntu2.1
	22.04 LTS jammy	Fixed 1:9.18.18-0ubuntu0.22.04.2
	20.04 LTS focal	Fixed 1:9.16.48-0ubuntu0.20.04.1
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected
isc-dhcp	25.04 plucky	Not affected
	24.10 oracular	Not affected
	24.04 LTS noble	Not affected
	23.10 mantic	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected
bind9-libs	25.04 plucky	Not in release
	24.10 oracular	Not in release
	24.04 LTS noble	Not in release
	23.10 mantic	Not in release
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release

Notes

alexmurray

As of isc-dhcp-4.4.3-1, isc-dhcp vendors bind9 libs

mdeslaur

9.11.x in isc-dhcp and bind9-libs not affected

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
bind9	Upstream: https://ftp.isc.org/isc/bind9/9.16.48/patches/0002-CVE-2023-5517.patch

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H