CVE-2026-11331 (GCVE-0-2026-11331)

Vulnerability from cvelistv5 – Published: 2026-07-22 14:10 – Updated: 2026-07-22 18:54
VLAI
Title
Potential wildcard CNAME RPZ policy bypass
Summary
An attacker who knows (or guesses) that a resolver uses RPZ with wildcard CNAME policies can craft query names long enough to trigger a NAMETOOLONG error condition during RPZ processing. This is not handled correctly and may lead to defeating the RPZ rule. It also may lead to an unexpected exit of the BIND 9 software. This issue affects BIND 9 versions 9.16.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.16.8-S1 through 9.18.50-S1, 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:H/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-790 - Improper Filtering of Special Elements
Assigner
isc
References
Impacted products
Vendor Product Version
ISC BIND 9 Affected: 9.16.0 , ≤ 9.18.50 (custom)
Affected: 9.20.0 , ≤ 9.20.24 (custom)
Affected: 9.21.0 , ≤ 9.21.23 (custom)
Affected: 9.16.8-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 Laith Mash'al (0xmshal) 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.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.