SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2023-2828

It has been discovered that the effectiveness of the cache-cleaning algorithm used in `named` can be severely diminished by querying the resolver for specific RRsets in a certain order, effectively allowing the configured `max-cache-size` limit to be…

HIGH 7.5EPSS 3.78%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (3.78%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Every `named` instance configured to run as a recursive resolver maintains a cache database holding the responses to the queries it has recently sent to authoritative servers. The size limit for that cache database can be configured using the `max-cache-size` statement in the configuration file; it defaults to 90% of the total amount of memory available on the host. When the size of the cache reaches 7/8 of the configured limit, a cache-cleaning algorithm starts to remove expired and/or least-recently used RRsets from the cache, to keep memory use below the configured limit. It has been discovered that the effectiveness of the cache-cleaning algorithm used in `named` can be severely diminished by querying the resolver for specific RRsets in a certain order, effectively allowing the configured `max-cache-size` limit to be significantly exceeded. This issue affects BIND 9 versions 9.11.0 through 9.16.41, 9.18.0 through 9.18.15, 9.19.0 through 9.19.13, 9.11.3-S1 through 9.16.41-S1, and 9.18.11-S1 through 9.18.15-S1.

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
3.78% probability · 89th percentile
CISA KEV
Not listed
Weakness
CWE-770
Affected
isc/bind · debian/debian linux · fedoraproject/fedora · netapp/active iq unified manager · netapp/h500s firmware · netapp/h700s firmware · netapp/h410s firmware · netapp/h410c firmware · netapp/h300s firmware
Source
security-officer@isc.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.