CVE-2026-13321 (GCVE-0-2026-13321)

Vulnerability from cvelistv5 – Published: 2026-07-22 14:16 – Updated: 2026-07-22 18:51
VLAI
Title
DNSSEC Validation Bypass via Out-of-Zone NSEC Next Field
Summary
The BIND resolver accepts validly-signed NSEC records where the "Next Domain Name" field points outside the signer's zone. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.
Severity
8.6 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-346 - Origin Validation Error
Assigner
isc
References
Impacted products
Vendor Product Version
ISC BIND 9 Affected: 9.11.0 , ≤ 9.18.50 (custom)
Affected: 9.20.0 , ≤ 9.20.24 (custom)
Affected: 9.21.0 , ≤ 9.21.23 (custom)
Affected: 9.11.3-S1 , ≤ 9.18.50-S1 (custom)
Affected: 9.20.9-S1 , ≤ 9.20.24-S1 (custom)
Create a notification for this product.
Date Public
2026-07-22 00:00
Credits
ISC would like to thank Qifan Zhang of Palo Alto Networks for bringing this vulnerability to our attention.
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

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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.