Use After Free in Powerdns Dnsdist

CVE-2025-30194

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.

Vulnerability class: Use-After-Free

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.022 (82.2th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 82nd percentile — 82.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-30194: held from 0.022 to 0.022.

EPSS over last 30 days · oldest: 0.022 · newest: 0.022 · change: +0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-30194?
CVE-2025-30194 is a high-severity vulnerability in Powerdns Dnsdist, classified under Use After Free. CVSS score: 7.5/10. Published 2025-04-29.
How severe is CVE-2025-30194?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2025-30194 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.