CVE-2023-6516

Specific recursive query patterns may lead to an out-of-memory condition

Description

To keep its cache database efficient, `named` running as a recursive resolver occasionally attempts to clean up the database. It uses several methods, including some that are asynchronous: a small chunk of memory pointing to the cache element that can be cleaned up is first allocated and then queued for later processing. It was discovered that if the resolver is continuously processing query patterns triggering this type of cache-database maintenance, `named` may not be able to handle the cleanup events in a timely manner. This in turn enables the list of queued cleanup events to grow infinitely large over time, allowing the configured `max-cache-size` limit to be significantly exceeded. This issue affects BIND 9 versions 9.16.0 through 9.16.45 and 9.16.8-S1 through 9.16.45-S1.

Remediation

Solution:

  • Upgrade to the patched release most closely related to your current version of BIND 9: 9.16.48 or 9.16.48-S1.

Workaround:

  • No workarounds known.

Categories

7.5
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.11%
Vendor Advisory isc.org
Affected: ISC BIND 9
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-6516?
CVE-2023-6516 has been scored as a high severity vulnerability.
How to fix CVE-2023-6516?
To fix CVE-2023-6516: Upgrade to the patched release most closely related to your current version of BIND 9: 9.16.48 or 9.16.48-S1.
Is CVE-2023-6516 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-6516 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-2023-6516?
CVE-2023-6516 affects ISC BIND 9.
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