VDB-384235 · CVE-2026-59901 · GCVE-0-2026-59901

Netty prior 4.1.136.Final/4.2.16.Final Bzip2Decoder Bzip2BlockDecompressor.read denial of service

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.1	$0-$5k	1.69

Summaryinfo

A vulnerability was found in Netty. It has been classified as problematic. Impacted is the function Bzip2BlockDecompressor.read of the component Bzip2Decoder. This manipulation causes denial of service. This vulnerability is registered as CVE-2026-59901. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in Netty. It has been declared as problematic. Affected by this vulnerability is the function Bzip2BlockDecompressor.read of the component Bzip2Decoder. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-59901 since 07/07/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

Upgrading to version 4.1.136.Final or 4.2.16.Final eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Name

Netty

Website

Product: https://github.com/netty/netty/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Netty 4.1.136.Final/4.2.16.Final

Timelineinfo

07/07/2026 CVE reserved
07/29/2026 +22 days Advisory disclosed
07/29/2026 +0 days VulDB entry created
07/29/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-59901 (🔒)
GCVE (CVE): GCVE-0-2026-59901
GCVE (VulDB): GCVE-100-384235

Entryinfo

Created: 07/29/2026 20:23
Changes: 07/29/2026 20:23 (54)
Complete: 🔍
Cache ID: 216::103