Vulnerability · Published May 20, 2025 · Assigned by OX
CVE-2025-30193Denial of service via crafted TCP exchange
High 7.5
In plain English
A high-severity security flaw in DNSdist from PowerDNS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 50% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
In some circumstances, when DNSdist is configured to allow an unlimited number of queries on a single, incoming TCP connection from a client, an attacker can cause a denial of service by crafting a TCP exchange that triggers an exhaustion of the stack and a crash of DNSdist, causing a denial of service. The remedy is: upgrade to the patched 1.9.10 version. A workaround is to restrict the maximum number of queries on incoming TCP connections to a safe value, like 50, via the setMaxTCPQueriesPerConnection setting. We would like to thank Renaud Allard for bringing this issue to our attention.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.21 | dnsdist | 1.9.10-r0 | ALPINE-CVE-2025-30193 |
| Alpine:v3.22 | dnsdist | 1.9.10-r0 | ALPINE-CVE-2025-30193 |
| Alpine:v3.23 | dnsdist | 1.9.10-r0 | ALPINE-CVE-2025-30193 |
| Alpine:v3.24 | dnsdist | 1.9.10-r0 | ALPINE-CVE-2025-30193 |
| Debian:12 | dnsdist | no fix listed | DEBIAN-CVE-2025-30193 |
| Debian:13 | dnsdist | 1.9.10-1 | DEBIAN-CVE-2025-30193 |
| Debian:14 | dnsdist | 1.9.10-1 | DEBIAN-CVE-2025-30193 |
| Ubuntu:25.10 | dnsdist | 1.9.10-1ubuntu0.1 | USN-8037-1 |
Affected products (as reported)
Weakness: CWE-674 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H