CVE-2026-40209
Medium
Description
An attacker might be able to cause outgoing TCP connections to backend to be stuck until a timeout occurs instead of being released immediately, by sending IXFR queries. This could be used to cause a denial of service if there is a limit to the number of concurrent connections to this backend, or if the process runs out of file descriptors.
SeverityMedium
CVSS5.3
Exploit probability—
ProductDNSdist
PublishedJun 25, 2026
First seenJun 25, 2026
Weakness typeCWE-772CWE-772
How to fix
Update
- PowerDNS DNSdist1.9.15, 2.0.7 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| PowerDNS DNSdist | 1.9.0 ≤ v < 1.9.15, 2.0.0 ≤ v < 2.0.7 | 1.9.15, 2.0.7 |
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