CVE-2020-8622

A truncated TSIG response can lead to an assertion failure

Description

In BIND 9.0.0 -> 9.11.21, 9.12.0 -> 9.16.5, 9.17.0 -> 9.17.3, also affects 9.9.3-S1 -> 9.11.21-S1 of the BIND 9 Supported Preview Edition, An attacker on the network path for a TSIG-signed request, or operating the server receiving the TSIG-signed request, could send a truncated response to that request, triggering an assertion failure, causing the server to exit. Alternately, an off-path attacker would have to correctly guess when a TSIG-signed request was sent, along with other characteristics of the packet and message, and spoof a truncated response to trigger an assertion failure, causing the server to exit.

Remediation

Solution:

  • Upgrade to the patched release most closely related to your current version of BIND: BIND 9.11.22 BIND 9.16.6 BIND 9.17.4 BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers. BIND 9.11.22-S1

Workaround:

  • No workarounds known.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.45%
Vendor Advisory fedoraproject.org Vendor Advisory ubuntu.com Vendor Advisory ubuntu.com Vendor Advisory debian.org Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory isc.org
Affected: ISC BIND9
Published at:
Updated at:

References

Link Tags
https://kb.isc.org/docs/cve-2020-8622 vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DQN62GBMCIC5AY4KYADGXNKVY6AJKSJE/ vendor advisory
https://usn.ubuntu.com/4468-1/ third party advisory vendor advisory
https://usn.ubuntu.com/4468-2/ third party advisory vendor advisory
https://www.debian.org/security/2020/dsa-4752 third party advisory vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZKAMJZXR66P6S5LEU4SN7USSNCWTXEXP/ vendor advisory
https://lists.debian.org/debian-lts-announce/2020/08/msg00053.html third party advisory mailing list
https://security.gentoo.org/glsa/202008-19 third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00041.html vendor advisory mailing list third party advisory
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00044.html vendor advisory mailing list third party advisory
https://www.oracle.com/security-alerts/cpuoct2021.html third party advisory patch
https://security.netapp.com/advisory/ntap-20200827-0003/ third party advisory
https://www.synology.com/security/advisory/Synology_SA_20_19 third party advisory

Frequently Asked Questions

What is the severity of CVE-2020-8622?
CVE-2020-8622 has been scored as a medium severity vulnerability.
How to fix CVE-2020-8622?
To fix CVE-2020-8622: Upgrade to the patched release most closely related to your current version of BIND: BIND 9.11.22 BIND 9.16.6 BIND 9.17.4 BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers. BIND 9.11.22-S1
Is CVE-2020-8622 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-8622 is being actively exploited. 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-2020-8622?
CVE-2020-8622 affects ISC BIND9.
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