CVE-2026-59901

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/netty/netty/security/advisories/GHSA-558v-64gr-wgg4	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:netty:netty::::::::
	cpe:2.3:a:netty:netty::::::::

History

06 Aug 2026, 20:29

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
CPE		cpe:2.3:a:netty:netty::::::::
References	~~() https://github.com/netty/netty/security/advisories/GHSA-558v-64gr-wgg4 -~~	() https://github.com/netty/netty/security/advisories/GHSA-558v-64gr-wgg4 - Vendor Advisory
First Time		Netty netty Netty

29 Jul 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-29 18:16

Updated : 2026-08-06 20:29

NVD link : CVE-2026-59901

Mitre link : CVE-2026-59901

CVE.ORG link : CVE-2026-59901

JSON object : View

Products Affected

netty

netty

CWE

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

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