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 · CISA-ADP (v2.0.3)
Decision recorded 2026-04-22 14:51 UTC
CWE
  • Allocation of Resources Without Limits or Throttling
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
OX CNA under the mitre root
CNA scorecard C 63/100 over 52 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
PowerDNS DNSdist Affected: 1.9.0 , < 1.9.13 (semver)
Affected: 2.0.0 , < 2.0.4 (semver)
guessed Create a notification for this product.
Date Public
2026-04-21 22:00
Credits
Salvor Labs - https://salvor.fr
Show details on NVD website
To clipboard 

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