CVE-2026-40211 (GCVE-0-2026-40211)

Vulnerability from cvelistv5 – Published: 2026-06-25 12:23 – Updated: 2026-06-25 13:45
VLAI?
Title
Denial of service via crafted DoH3 queries
Summary
An attacker can send crafted DNS over HTTP/3 queries, triggering an exception that prevents some buffer from being freed right away. The buffer will be freed at the end of the QUIC connection, but on some setups it might be possible to open enough concurrent DoH3 streams to trigger an out-of-memory condition, resulting in a denial of service.
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 , < 1.9.15 (semver)
Affected: 2.0.0 , < 2.0.7 (semver)
Create a notification for this product.
Credits
Mehtab Zafar
Show details on NVD website
To clipboard 

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