What’s Vulnerable › Vulnerabilities
CVE-2026-33254: Resource exhaustion via DoQ/DoH3 connections
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.4% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-04-22 · updated 2026-10-26
- Weakness: CWE-770
Description
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.
Affected products
- PowerDNS DNSdist: from 1.9.0 before 1.9.13; from 2.0.0 before 2.0.4 — fixed in 1.9.13, 2.0.4
How to fix
Upgrade to a fixed version: PowerDNS DNSdist 1.9.13, 2.0.4. Check the vendor advisory for mitigations.
References
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