3.7
LOW CVSS 3.1
CVE-2026-40208
Denial of service via DoH3 queries
Description

An attacker might be able to delay the processing of DoH3 queries by sending DoH3 GET queries with an invalid DATA frame.

INFO

Published Date :

June 25, 2026, 12:22 p.m.

Last Modified :

June 25, 2026, 12:22 p.m.

Remotely Exploit :

Yes !

Source :

OX
Affected Products

The following products are affected by CVE-2026-40208 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Powerdns dnsdist
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 LOW 8ce71d90-2354-404b-a86e-bec2cc4e6981
CVSS 3.1 LOW [email protected]
Solution
Implement DoH3 query validation to prevent DoS attacks.
  • Validate incoming DoH3 GET queries.
  • Ensure DATA frames are correctly formatted.
  • Reject malformed queries promptly.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-40208 vulnerability anywhere in the article.

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.