CVE-2019-6470

Public Exploit
dhcpd: use-after-free error leads crash in IPv6 mode when using mismatched BIND libraries

Description

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.

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.20%
Vendor Advisory redhat.com
Affected: Multiple, non-ISC dhcpd
Published at:
Updated at:

References

Link Tags
https://access.redhat.com/errata/RHSA-2019:2060 third party advisory
https://lists.opensuse.org/opensuse-security-announce/2019-10/msg00049.html third party advisory mailing list
https://lists.opensuse.org/opensuse-security-announce/2019-10/msg00048.html third party advisory mailing list
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=896122 mailing list exploit third party advisory
https://access.redhat.com/errata/RHSA-2019:3525 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2019-6470?
CVE-2019-6470 has been scored as a medium severity vulnerability.
How to fix CVE-2019-6470?
To fix CVE-2019-6470, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-6470 being actively exploited in the wild?
It is possible that CVE-2019-6470 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2019-6470?
CVE-2019-6470 affects Multiple, non-ISC dhcpd.
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