CVE-2026-11605 (GCVE-0-2026-11605)

Vulnerability from cvelistv5 – Published: 2026-07-22 14:11 – Updated: 2026-07-22 18:53
VLAI
Title
Unnecessary validation of DNSSEC signed records
Summary
The issue is a resource exhaustion vulnerability associated with DNSSEC validation. BIND always validates all RRSIG records in an answer, even if they are not strictly needed. A query to an authoritative server/zone which returns many valid but superfluous RRSIG records causes the validator to waste disproportionate CPU time. This issue affects BIND 9 versions 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, and 9.20.9-S1 through 9.20.24-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 (v2.0.3)
CWE
  • CWE-408 - Incorrect Behavior Order - Early Amplification
Assigner
isc
References
Impacted products
Vendor Product Version
ISC BIND 9 Affected: 9.20.0 , ≤ 9.20.24 (custom)
Affected: 9.21.0 , ≤ 9.21.23 (custom)
Affected: 9.20.9-S1 , ≤ 9.20.24-S1 (custom)
Create a notification for this product.
Date Public
2026-07-22 00:00
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • 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.


Detection rules are retrieved from Rulezet.