Low severity · published Jun 25, 2026
CVE-2026-40208
Denial of service via DoH3 queries
3.7
CVSS
0.4%
EPSS
No
On KEV
Description
An attacker might be able to delay the processing of DoH3 queries by sending DoH3 GET queries with an invalid DATA frame.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 34% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DN
DNSdist · PowerDNS
1.9.0 before 1.9.15; 2.0.0 before 2.0.7 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40208
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40208
www.dnsdist.org
https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html
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