MajorCritical vulnerability

CVE-2026-123604 (CVSS 8.7)

NVD · officialPublished Nov 8, 2026Risk 37/100EPSS 0.3%

Hickory DNS hickory-resolver 0.26.0-beta.1 before 0.26.2 contains an unbounded retry loop in NameServerPool::try_send, which re-queues truncated (TC) responses without checking the answering transport or counting iterations. A malicious authoritative server returning TC=1 on every transport keeps the resolver spinning on a persistent TCP connection until the 5-second request deadline expires, causing resource exhaustion.

Technical details

CVSS

8.7

AV:NetworkAC:LowPR:NoneUI:None

Evidence and sources

This record is attributed to NVD. Exploitation status and remediation guidance are kept separate from the vulnerability's technical severity.

Open primary source