High severity · published Apr 29, 2025
CVE-2025-30194
Denial of service via crafted DoH exchange
7.5
CVSS
2.2%
EPSS
No
On KEV
Description
When DNSdist is configured to provide DoH via the nghttp2 provider, an attacker can cause a denial of service by crafting a DoH exchange that triggers an illegal memory access (double-free) and crash of DNSdist, causing a denial of service.
The remedy is: upgrade to the patched 1.9.9 version.
A workaround is to temporarily switch to the h2o provider until DNSdist has been upgraded to a fixed version.
We would like to thank Charles Howes for bringing this issue to our attention.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.2% · higher than 83% 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 1.9.9 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-30194
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-30194
dnsdist.org
https://dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2025-02.html
www.openwall.com
http://www.openwall.com/lists/oss-security/2025/04/29/1
www.vicarius.io
https://www.vicarius.io/vsociety/posts/cve-2025-30194-detection-dnsdist-vulnerability
www.vicarius.io
https://www.vicarius.io/vsociety/posts/cve-2025-30194-mitigate-dnsdist-vulnerability
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