CVE-2026-81736 (GCVE-0-2026-81736)

Vulnerability from cvelistv5 – Published: 2026-09-16 13:44 – Updated: 2026-09-17 18:46
VLAI
Title
Remote CPU denial of service through cached SVCB/HTTPS AliasMode trees
Summary
If a BIND resolver has cached a tree of SVCB/HTTPS AliasMode records, and is then queried for the root of that tree, the resolver will spend disproportionate CPU time constructing the response. This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.18.11-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-17 18:45 UTC
CWE
  • CWE-1050 - Excessive Platform Resource Consumption within a Loop
Assigner
isc CNA under the mitre root
CNA scorecard A 95/100 over 33 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
ISC BIND 9 Affected: 9.18.0 , ≤ 9.18.50 (custom)
Affected: 9.20.0 , ≤ 9.20.27 (custom)
Affected: 9.21.0 , ≤ 9.21.25 (custom)
Affected: 9.18.11-S1 , ≤ 9.18.50-S1 (custom)
Affected: 9.20.9-S1 , ≤ 9.20.27-S1 (custom)
    cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
    cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
    cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
    cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
    cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-16 00:00
Credits
ISC would like to thank Henrique Pereira for bringing this vulnerability to our attention.
Show details on NVD website
To clipboard 

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