Riskcovery

CVE-2026-42579

Netty: DNS Codec Input Validation Bypass in Netty (Encoder + Decoder)

State
Published
Severity
7.5 High
Published
May 13, 2026
Updated
Sep 18, 2026
Reserved
Apr 28, 2026

Read the record on cve.org

Description

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's DNS codec does not enforce RFC 1035 domain name constraints during either encoding or decoding. This creates a bidirectional attack surface: malicious DNS responses can exploit the decoder, and user-influenced hostnames can exploit the encoder. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

Scores

CVSSScoreVectorSource
3.17.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:NGitHub_M
3.17.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nredhat-SADP

Weaknesses

  • CWE-20 Improper Input Validation
  • CWE-400 Uncontrolled Resource Consumption
  • CWE-626 Null Byte Interaction Error (Poison Null Byte)
  • CWE-1286 Improper Validation of Syntactic Correctness of Input

Affected Products

ProductVersions
nettynetty
  • >= 4.2.0.Alpha1, < 4.2.13.FinalAffected
  • < 4.1.133.FinalAffected

References

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