CVE-2023-2828 named's configured cache size limit can be significantly exceeded

2023-06-2116:26:07

isc

www.cve.org

named

cache

limit

exceeded

queries

cve-2023-2828

bind

9.11

9.16.41

9.18.15

9.19.13

9.11.3-s1

9.16.41-s1

7.5 High

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

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

7.9 High

AI Score

Confidence

High

0.001 Low

EPSS

Percentile

47.8%

JSON

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.

CNA Affected

[
  {
    "vendor": "ISC",
    "product": "BIND 9",
    "versions": [
      {
        "version": "9.11.0",
        "lessThanOrEqual": "9.16.41",
        "status": "affected",
        "versionType": "custom"
      },
      {
        "version": "9.18.0",
        "lessThanOrEqual": "9.18.15",
        "status": "affected",
        "versionType": "custom"
      },
      {
        "version": "9.19.0",
        "lessThanOrEqual": "9.19.13",
        "status": "affected",
        "versionType": "custom"
      },
      {
        "version": "9.11.3-S1",
        "lessThanOrEqual": "9.16.41-S1",
        "status": "affected",
        "versionType": "custom"
      },
      {
        "version": "9.18.11-S1",
        "lessThanOrEqual": "9.18.15-S1",
        "status": "affected",
        "versionType": "custom"
      }
    ],
    "defaultStatus": "unaffected"
  }
]