CVE-2020-8616

Public Exploit
BIND does not sufficiently limit the number of fetches performed when processing referrals

Description

A malicious actor who intentionally exploits this lack of effective limitation on the number of fetches performed when processing referrals can, through the use of specially crafted referrals, cause a recursing server to issue a very large number of fetches in an attempt to process the referral. This has at least two potential effects: The performance of the recursing server can potentially be degraded by the additional work required to perform these fetches, and The attacker can exploit this behavior to use the recursing server as a reflector in a reflection attack with a high amplification factor.

Remediation

Solution:

  • Upgrade to the patched release most closely related to your current version of BIND: BIND 9.11.19 BIND 9.14.12 BIND 9.16.3 BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers. BIND 9.11.19-S1

Workaround:

  • None

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 9.32% Top 10%
Vendor Advisory debian.org Vendor Advisory ubuntu.com Vendor Advisory ubuntu.com Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory isc.org
Affected: ISC BIND9
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2020-8616?
CVE-2020-8616 has been scored as a high severity vulnerability.
How to fix CVE-2020-8616?
To fix CVE-2020-8616: Upgrade to the patched release most closely related to your current version of BIND: BIND 9.11.19 BIND 9.14.12 BIND 9.16.3 BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers. BIND 9.11.19-S1
Is CVE-2020-8616 being actively exploited in the wild?
It is possible that CVE-2020-8616 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~9% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-8616?
CVE-2020-8616 affects ISC BIND9.
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