CVE-2019-6470

Publication date 3 May 2019

Last updated 24 July 2024


Ubuntu priority

Cvss 3 Severity Score

7.5 · High

Score breakdown

There had existed in one of the ISC BIND libraries a bug in a function that was used by dhcpd when operating in DHCPv6 mode. There was also a bug in dhcpd relating to the use of this function per its documentation, but the bug in the library function prevented this from causing any harm. All releases of dhcpd from ISC contain copies of this, and other, BIND libraries in combinations that have been tested prior to release and are known to not present issues like this. Some third-party packagers of ISC software have modified the dhcpd source, BIND source, or version matchup in ways that create the crash potential. Based on reports available to ISC, the crash probability is large and no analysis has been done on how, or even if, the probability can be manipulated by an attacker. Affects: Builds of dhcpd versions prior to version 4.4.1 when using BIND versions 9.11.2 or later, or BIND versions with specific bug fixes backported to them. ISC does not have access to comprehensive version lists for all repackagings of dhcpd that are vulnerable. In particular, builds from other vendors may also be affected. Operators are advised to consult their vendor documentation.

Read the notes from the security team

Status

Package Ubuntu Release Status
isc-dhcp 19.04 disco
Not affected
18.10 cosmic
Fixed 4.3.5-3ubuntu9.1
18.04 LTS bionic
Fixed 4.3.5-3ubuntu7.1
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected

Notes


mdeslaur

issue in isc-dhcp was introduced by the following change in bind in bionic+: https://gitlab.isc.org/wpk/bind9/commit/65a483106e45704e19781bfe4f4634db4f77562e

Patch details

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

Package Patch details
isc-dhcp

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

References

Related Ubuntu Security Notices (USN)

Other references