Search: CVE-2026-80213

CVE-2026-80213 is a numeric truncation error in the Ruby resolv gem before version 0.7.2. The vulnerability arises because the DNS label length is written as a single octet without validating its range, allowing labels longer than 255 octets to be encoded incorrectly. This causes the wire format of DNS queries to differ from the intended domain name, potentially bypassing allowlist and egress checks. The issue can lead to recursive resolvers caching responses under attacker-controlled names and DNS logs recording misleading domain names.