CVE-2026-33254 (GCVE-0-2026-33254)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:45 – Updated: 2026-04-22 14:51
VLAI
Title
Resource exhaustion via DoQ/DoH3 connections
Summary
An attacker can create a large number of concurrent DoQ or DoH3 connections, causing unlimited memory allocation in DNSdist and leading to a denial of service. DOQ and DoH3 are disabled by default.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • Allocation of Resources Without Limits or Throttling
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
OX
References
Impacted products
Vendor Product Version
PowerDNS DNSdist Affected: 1.9.0 , < 1.9.13 (semver)
Affected: 2.0.0 , < 2.0.4 (semver)
Create a notification for this product.
Date Public
2026-04-21 22:00
Credits
Salvor Labs - https://salvor.fr
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.