CVE-2026-11331 (GCVE-0-2026-11331)
Vulnerability from cvelistv5 – Published: 2026-07-22 14:10 – Updated: 2026-07-22 18:54
VLAI
EPSS
VEX
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)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-22 18:54 UTC
CWE
- CWE-790 - Improper Filtering of Special Elements
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://kb.isc.org/docs/cve-2026-11331 | vendor-advisory |
| https://downloads.isc.org/isc/bind9/9.20.26 | patch |
| https://downloads.isc.org/isc/bind9/9.21.24 | patch |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| 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) 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:*:*:*:*:*:*:*:* |
Date Public
2026-07-22 00:00
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
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.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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