named configured to answer from stale cache may terminate unexpectedly while processing RRSIG queries

Description

BIND 9 resolver can crash when stale cache and stale answers are enabled, option `stale-answer-client-timeout` is set to a positive integer, and the resolver receives an RRSIG query. 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.

Scores

EPSS (exploitation in 30 days)

48.4% · top 1.1% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: yes · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.

Weakness

• n/a
• CWE-20 Improper Input Validation (opens in a new tab)All about CWE-20 and its CVEs

Affected products

• ISC · BIND 9

  • affected 9.16.12 – ≤ 9.16.36
  • affected 9.18.0 – ≤ 9.18.10
  • affected 9.19.0 – ≤ 9.19.8
  • affected 9.16.12-S1 – ≤ 9.16.36-S1

What to do

Solution: Upgrade to the patched release most closely related to your current version of BIND 9: 9.16.37, 9.18.11, 9.19.9, or 9.16.37-S1.

Workaround: Setting `stale-answer-client-timeout` to `0` or to `off/disabled` will prevent BIND from crashing due to this issue.

Exploitation: We are not aware of any active exploits.

References (1)

• CVE-2022-3736 (opens in a new tab)vendor-advisoryx_transferred

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2022-3736](https://trackcve.app/badge/CVE-2022-3736.svg)](https://trackcve.app/cve/CVE-2022-3736)

Record last updated 1 Apr 2025, 14:10 UTC.