Is CVE-2026-40208 in the CISA KEV catalog?

No. CVE-2026-40208 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-40208?

CVE-2026-40208 has a CVSS v3 base score of 3.7 (LOW).

What is the EPSS score for CVE-2026-40208?

CVE-2026-40208 has an EPSS score of 0.29% (20th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2026-40208?

Upgrade dnsdist on debian 13 to 1.9.15-0+deb13u1 or later.

CVE & CISA-KEV Catalog

CVE-2026-40208

LOW

3.7

CVSS v3

NVD

Description

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

CWE-705

How to fix

Remediation Available

dnsdistDebian

Fixed in:1.9.15-0+deb13u1CVE-2026-40208

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityHigh

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityNone

AvailabilityLow

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

Exploit Intelligence

0.29%probability of exploitation in 30 days

20thpercentile

Low risk: more likely to be exploited than 20% of all known CVEs.

References

Other references1

dnsdist.org

Embed a live status badge for CVE-2026-40208

Markdown

[![CVE-2026-40208](https://tridentstack.com/cve/badge/CVE-2026-40208.svg)](https://tridentstack.com/cve/CVE-2026-40208)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-40208"><img src="https://tridentstack.com/cve/badge/CVE-2026-40208.svg" alt="CVE-2026-40208"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-25.