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… (CVE-2026-59901)
Netty versions prior to 4.1.136.Final and 4.2.16.Final contain a vulnerability in the Bzip2Decoder handler that allows a denial-of-service (DoS) attack. This occurs when processing a malformed bzip2 stream, causing the event-loop thread to enter an infinite loop due to a flaw in the run-length encoding state machine. The issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.
AI Analysis
Technical Summary
The Bzip2Decoder handler in Netty's compression codec pipeline is vulnerable to a denial-of-service attack triggered by a malformed bzip2 stream that causes the event-loop thread to be permanently captured in an infinite loop. The root cause is a flaw in the run-length encoding (RLE) state machine within the Bzip2BlockDecompressor.read() method. This vulnerability affects Netty versions before 4.1.136.Final and 4.2.16.Final and has been addressed in these fixed versions.
Potential Impact
An attacker can cause a denial-of-service condition by sending a specially crafted bzip2 compressed stream that triggers an infinite loop in the event-loop thread, effectively halting processing of other events. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
Upgrade Netty to version 4.1.136.Final or later, or 4.2.16.Final or later, where the vulnerability has been fixed. No other mitigation or workaround is indicated by the vendor advisory.
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… (CVE-2026-59901)
Description
Netty versions prior to 4.1.136.Final and 4.2.16.Final contain a vulnerability in the Bzip2Decoder handler that allows a denial-of-service (DoS) attack. This occurs when processing a malformed bzip2 stream, causing the event-loop thread to enter an infinite loop due to a flaw in the run-length encoding state machine. The issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.
CVSS v3.1
Score 7.5high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Bzip2Decoder handler in Netty's compression codec pipeline is vulnerable to a denial-of-service attack triggered by a malformed bzip2 stream that causes the event-loop thread to be permanently captured in an infinite loop. The root cause is a flaw in the run-length encoding (RLE) state machine within the Bzip2BlockDecompressor.read() method. This vulnerability affects Netty versions before 4.1.136.Final and 4.2.16.Final and has been addressed in these fixed versions.
Potential Impact
An attacker can cause a denial-of-service condition by sending a specially crafted bzip2 compressed stream that triggers an infinite loop in the event-loop thread, effectively halting processing of other events. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
Upgrade Netty to version 4.1.136.Final or later, or 4.2.16.Final or later, where the vulnerability has been fixed. No other mitigation or workaround is indicated by the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-558v-64gr-wgg4
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-59901"]
- Ecosystems
- ["Maven"]
- Database Specific Severity
- HIGH
- Cvss Version
- 4.0
Threat ID: 6a6150d39c2644c7f8da06d8
Added to database: 07/22/2026, 23:22:59 UTC
Last enriched: 08/08/2026, 16:58:49 UTC
Last updated: 09/05/2026, 17:30:07 UTC
Views: 154
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