CVE-2026-42579: high-severity vulnerability in netty
Netty: DNS Codec Input Validation Bypass in Netty (Encoder + Decoder)
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No sign of exploitation. No public exploitation artifact known so far.
Netty's DNS handling doesn't properly validate domain names according to standard rules, allowing attackers to send crafted DNS responses or inject malicious hostnames that bypass safety checks.
The DNS codec in Netty versions prior to 4.2.13.Final and 4.1.133.Final fails to enforce RFC 1035 domain name constraints in both encoder and decoder paths. Attackers can leverage malicious DNS responses (decoder attack vector) or user-controlled hostnames (encoder attack vector) to trigger input validation bypass, potentially leading to denial of service or unexpected behavior.
In the same product, most dangerous first.