CVE-2026-33254 Details
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.
A denial-of-service vulnerability has been identified in PowerDNS DNSdist versions through 2.0.3 and 1.9.12. The issue arises when an attacker creates a large number of concurrent DoQ or DoH3 connections, leading to unlimited memory allocation and causing the application to become unresponsive. Although DoQ and DoH3 are disabled by default, this vulnerability can still be exploited if these protocols are enabled.
Users can upgrade to PowerDNS DNSdist versions 1.9.13 or 2.0.4, where this vulnerability has been patched. Alternatively, DoQ and DoH3 can be disabled.
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Apr 22, 2026References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-04.html | [email protected] | Vendor Advisory |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-770 | Allocation of Resources Without Limits or Throttling | CISA-ADP |
Affected Products
| Product | Versions |
|---|---|
| powerdns dnsdist | >= 1.9.0, < 1.9.13 >= 2.0.0, < 2.0.4 |
CPE
Remediation
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Change History
5 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Apr 27, 2026 | Initial Analysis | [email protected] |
| Apr 22, 2026 | CVE Modified | CISA-ADP |
| Apr 22, 2026 | New CVE Received | [email protected] |