CVE-2025-30193: high-severity vulnerability in PowerDNS DNSdist
Denial of service via crafted TCP exchange
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.6%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
PowerDNS · DNSdistRelated CVEs — PowerDNS DNSdist
In the same product, most dangerous first.
CVE-2025-30194HIGHDenial of service via crafted DoH exchangeEPSS 2.3%CVE-2024-25581HIGHTransfer requests received over DoH can lead to a denial of service in DNSdistEPSS 1.1%CVE-2026-33598MEDIUMOut-of-bounds read in cache inspection via LuaEPSS 1.1%CVE-2026-24028MEDIUMOut-of-bounds read when parsing DNS packets via LuaEPSS 1.1%CVE-2026-40210MEDIUMOut-of-bounds read in SetMacAddrActionEPSS 0.7%CVE-2026-33602MEDIUMOff-by-one access when processing crafted UDP responsesEPSS 0.7%