cbcvebase.
CVE-2022-3736
published 2023-01-26

CVE-2022-3736: 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…

PriorityP358high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
48.43%
98.7th percentile
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.

Affected

32 ranges· showing 25
VendorProductVersion rangeFixed in
debianbind9< bind9 1:9.18.11-1 (bookworm)bind9 1:9.18.11-1 (bookworm)
iscbind
iscbind
iscbind
iscbind
iscbind
iscbind
iscbind>= 0 < 9.16.37-r09.16.37-r0
iscbind>= 0 < 9.16.37-r09.16.37-r0
iscbind>= 0 < 9.16.37-r09.16.37-r0
iscbind>= 0 < 9.18.11-r09.18.11-r0
iscbind>= 0 < 9.18.11-r09.18.11-r0
iscbind>= 0 < 9.18.11-r09.18.11-r0
iscbind>= 0 < 9.18.11-r09.18.11-r0
iscbind>= 0 < 9.18.11-r09.18.11-r0
iscbind>= 0 < 9.18.11-r09.18.11-r0
iscbind>= 0 < 9.18.11-r09.18.11-r0
iscbind>= 9.16.12 < 9.16.379.16.37
iscbind>= 9.18.0 < 9.18.119.18.11
iscbind>= 9.19.0 < 9.19.99.19.9
iscbind9>= 0 < 1:9.16.37-1~deb11u11:9.16.37-1~deb11u1
iscbind9>= 0 < 1:9.18.11-11:9.18.11-1
iscbind9>= 0 < 1:9.18.11-11:9.18.11-1
iscbind9>= 0 < 1:9.18.11-11:9.18.11-1
iscbind9>= 0 < 1:9.16.1-0ubuntu2.121:9.16.1-0ubuntu2.12

Detection & IOCsextracted from sources · hover to see the quote

  • Trigger condition: BIND 9 resolver crashes when stale cache and stale answers are enabled, stale-answer-client-timeout is set to a positive integer, AND the resolver receives an RRSIG query — monitor for named process crashes under these conditions
  • Detect exploitation attempts by monitoring for RRSIG query types directed at BIND resolvers with stale-answer-client-timeout configured to a positive integer
  • The vulnerable code path was introduced in BIND 9.16.12 via the stale-answer-client-timeout option; flag any named instances running versions 9.16.12–9.16.36, 9.18.0–9.18.10, 9.19.0–9.19.8, or 9.16.12-S1–9.16.36-S1 with this option enabled
  • The flaw is specifically in the stale-answer-client-timeout implementation; audit named.conf for this option set to any positive integer as a risk indicator
  • ·Setting stale-answer-client-timeout to 0 or off/disabled fully mitigates the crash; only resolvers with a positive integer value for this option are vulnerable
  • ·Both stale cache AND stale answers must be enabled simultaneously alongside a positive stale-answer-client-timeout for the vulnerability to be triggerable — all three conditions are required
  • ·Red Hat Enterprise Linux 6, 7, and 8 ship BIND versions not affected by this CVE; only RHEL 9 and equivalent (e.g., Ubuntu 22.04 LTS, 22.10) carry vulnerable versions

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH
vendor_debian7.5HIGH
vendor_msrc7.5HIGH
vendor_redhat7.5HIGH
vendor_ubuntu7.5HIGH
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