CVE-2026-52686 (GCVE-0-2026-52686)

Vulnerability from cvelistv5 – Published: 2026-07-23 08:03 – Updated: 2026-07-23 13:56
VLAI
Title
Wildcard CNAME proof validation bypass
Summary
The issue is a DNSSEC validation bypass where wildcard expansion proofs (NSEC/NSEC3 records) are accepted without signature validation when the wildcard answer is a CNAME or DNAME record.
Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • Insufficient Verification of Data Authenticity
  • CWE-347 - Improper Verification of Cryptographic Signature
Assigner
OX
References
Impacted products
Vendor Product Version
PowerDNS Recursor Affected: 5.2.0 , < 5.2.12 (semver)
Affected: 5.3.0 , < 5.3.9 (semver)
Affected: 5.4.0 , < 5.4.4 (semver)
Create a notification for this product.
Date Public
2026-07-21 22:00
Credits
Qifan Zhang from Palo Alto Networks
Show details on NVD website
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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.