MajorCritical vulnerability
CVE-2026-123570 (CVSS 8.7)
NVD · officialPublished Nov 8, 2026Risk 37/100EPSS 0.4%
The DNS wire-format message parser in hickory-proto (Hickory DNS) 0.18 before 0.26.2 preallocates record vectors sized by the untrusted ANCOUNT, NSCOUNT, and ARCOUNT header fields before reading record data. Remote attackers can send a UDP datagram, or a spoofed response to a client/resolver, with these counts set to 65535, forcing about 18MB of allocation per message.
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.
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