CVE-2026-33602
MediumCVSS 6.5Exploitation Probability (EPSS)
Elevated risk54th percentile - higher than 54% of all known CVEs
Summary
A rogue backend can send a crafted UDP response with a query ID off by one relative to the maximum configured value, triggering an out-of-bounds write that leads to denial of service.
Risk Assessment
An attacker controlling a DNS backend can cause a service crash via the out-of-bounds write, resulting in name resolution unavailability. This may disrupt dependent systems.
Recommendation
Update the DNS resolver software to a version containing the fix. Consider limiting trust in backends and monitoring for anomalies in UDP responses.
Other vulnerabilities in DNS resolver
See all- CVE-2026-52686Low
Vulnerability in DNSSEC validation allows bypassing signature verification for wildcard expansion proofs (NSEC/NSEC3) when the answer is a CNAME or DNAME record.
- CVE-2026-46600High
Parsing an invalid SVCB or HTTPS RR can panic when the size of a parameter value overflows the message buffer.
Original NVD description (English source)
A rogue backend can send a crafted UDP response with a query ID off by one related to the maximum configured value, triggering an out-of-bounds write leading to a denial of service.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS