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CVE-2026-59901GHSA-558V-64GR-WGG4

Netty Bzip2Decoder: Infinite Loop in RLE State Machine Leads to Event-Loop Thread Hang

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 4.2.16.Final, 4.1.136.Final
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: yes
  • Technical impact: partial

Summary

Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, the `Bzip2Decoder` handler in Netty's compression codec pipeline is vulnerable to a denial-of-service attack through a malformed bzip2 stream that permanently captures the event-loop thread in an infinite loop. The vulnerability exists in the run-length encoding (RLE) state machine within [`Bzip2BlockDecompressor.read()`]. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: yes · Technical impact: partial

  3. Record last updated

Affected versions

  • netty netty

    From 4.2.0.Final · fixed in 4.2.16.Final; fixed in 4.1.136.Final

  • io.netty:netty-codec-compressionMaven

    From 4.2.0.Final · fixed in 4.2.16.Final

  • io.netty:netty-codecMaven

    fixed in 4.1.136.Final

References 1

GitHub · netty/netty