CVE-2025-30193

HIGHCVSS 7.5/10EPSS 0.56%

Last modified

CVE-2025-30193 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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.. EPSS estimates a 0.56% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1
7.5/10

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

EPSS Probability
0.56%

42.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

References

Timeline

Published
Last Modified
Status
Deferred

Frequently Asked Questions

What is CVE-2025-30193?
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.
How severe is CVE-2025-30193?
CVE-2025-30193 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.56% probability of exploitation in the next 30 days.
How do I fix CVE-2025-30193?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2025-30193?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST