CVE-2026-33594 (GCVE-0-2026-33594)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:48 – Updated: 2026-04-22 14:36
VLAI
Title
Outgoing DoH excessive memory allocation
Summary
A client can trigger excessive memory allocation by generating a lot of queries that are routed to an overloaded DoH backend, causing queries to accumulate into a buffer that will not be released until the end of the connection.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE
  • 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
Mehtab Zafar
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.
  • 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.