CVE-2026-59901
Published:July 29, 2026
Updated:August 04, 2026
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.
Affected Packages
io.netty:netty-codec-compression (JAVA):
Affected version(s) >=4.2.0.Final <4.2.16.FinalFix Suggestion:
Update to version 4.2.16.Finalio.netty:netty-codec (JAVA):
Affected version(s) >=4.0.0.Alpha1 <4.1.136.FinalFix Suggestion:
Update to version 4.1.136.FinalRelated Resources (6)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
Loop with Unreachable Exit Condition ('Infinite Loop')
EPSS
Base Score:
0.25