CVE-2026-81563 (GCVE-0-2026-81563)

Vulnerability from cvelistv5 – Published: 2026-09-16 14:00 – Updated: 2026-09-17 17:47
VLAI
Title
SVCB AliasMode additional-data error leaks qpcache references
Summary
A BIND resolver encountering an SVCB/HTTPS AliasMode record referencing 14 or more SVCB/HTTPS ServiceMode records may fail to properly deallocate internal resources. If this happens repeatedly, resource exhaustion will eventually prevent the resolver from performing new recursive lookups. 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 17:47 UTC
CWE
  • CWE-401 - Missing Release of Memory after Effective Lifetime
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 Samy Medjahed/Ap4sh for bringing this vulnerability to our attention.
Show details on NVD website
To clipboard 

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}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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