CVE-2023-6516

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.

CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-770 CWE-770

CWE-789 CWE-789

Affected Products

Vendor	Product	Versions
isc	bind	9.16.0 — 9.16.45
isc	bind	All
isc	bind	All
isc	bind	All
isc	bind	All
isc	bind	All
isc	bind	All
isc	bind	All
isc	bind	All
isc	bind	All
isc	bind	All
netapp	active_iq_unified_manager	All

References

Advisories & Patches

https://kb.isc.org/docs/cve-2023-6516 https://kb.isc.org/docs/cve-2023-6516

Other References

http://www.openwall.com/lists/oss-security/2024/02/13/1 https://lists.fedoraproject.org/archives/list/[email protected]/message/PNNHZSZPG2E7NBMBNYPGHCFI4V4XRWNQ/ https://lists.fedoraproject.org/archives/list/[email protected]/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/ https://security.netapp.com/advisory/ntap-20240503-0008/ http://www.openwall.com/lists/oss-security/2024/02/13/1 https://lists.fedoraproject.org/archives/list/[email protected]/message/PNNHZSZPG2E7NBMBNYPGHCFI4V4XRWNQ/ https://lists.fedoraproject.org/archives/list/[email protected]/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/ https://security.netapp.com/advisory/ntap-20240503-0008/

Frequently Asked Questions

What is CVE-2023-6516? +

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. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2023-6516? +

CVE-2023-6516 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2023-6516? +

CVE-2023-6516 affects products from isc, netapp, specifically: active_iq_unified_manager, bind. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-6516? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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