CVE-2022-3924 named configured to answer from stale cache may terminate unexpectedly at recursive-clients soft quota

2023-01-2521:39:49

isc

www.cve.org

cve-2022-3924

bind 9

resolver

terminate unexpectedly

stale cache

recursive clients

soft quota

assertion failure

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

7.6 High

AI Score

Confidence

High

0.001 Low

EPSS

Percentile

35.2%

JSON

This issue can affect BIND 9 resolvers with stale-answer-enable yes; that also make use of the option stale-answer-client-timeout, configured with a value greater than zero.

If the resolver receives many queries that require recursion, there will be a corresponding increase in the number of clients that are waiting for recursion to complete. If there are sufficient clients already waiting when a new client query is received so that it is necessary to SERVFAIL the longest waiting client (see BIND 9 ARM recursive-clients limit and soft quota), then it is possible for a race to occur between providing a stale answer to this older client and sending an early timeout SERVFAIL, which may cause an assertion failure.
This issue affects BIND 9 versions 9.16.12 through 9.16.36, 9.18.0 through 9.18.10, 9.19.0 through 9.19.8, and 9.16.12-S1 through 9.16.36-S1.

CNA Affected

[
  {
    "vendor": "ISC",
    "product": "BIND 9",
    "versions": [
      {
        "version": "9.16.12",
        "lessThanOrEqual": "9.16.36",
        "status": "affected",
        "versionType": "custom"
      },
      {
        "version": "9.18.0",
        "lessThanOrEqual": "9.18.10",
        "status": "affected",
        "versionType": "custom"
      },
      {
        "version": "9.19.0",
        "lessThanOrEqual": "9.19.8",
        "status": "affected",
        "versionType": "custom"
      },
      {
        "version": "9.16.12-S1",
        "lessThanOrEqual": "9.16.36-S1",
        "status": "affected",
        "versionType": "custom"
      }
    ],
    "defaultStatus": "unaffected"
  }
]