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. The vulnerability is triggered by 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. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.
CVSS v3.1
Score 7.5high
Affected software
pkg:deb/ubuntu/netty?arch=source&distro=esm-infra-legacy/trustypkg:deb/ubuntu/netty?arch=source&distro=esm-apps-legacy/xenialpkg:deb/ubuntu/netty?arch=source&distro=esm-apps/bionicpkg:deb/ubuntu/netty?arch=source&distro=esm-apps/focalpkg:deb/ubuntu/netty?arch=source&distro=esm-apps/jammypkg:deb/ubuntu/netty?arch=source&distro=esm-apps/noblepkg:deb/ubuntu/netty?arch=source&distro=stonkingpkg:deb/ubuntu/netty?arch=source&distro=esm-apps/resoluteRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-59901 affects the Bzip2Decoder handler in Netty's compression codec pipeline in versions prior to 4.1.136.Final and 4.2.16.Final. The vulnerability allows an attacker to cause a denial-of-service condition by sending a malformed bzip2 stream. The flaw lies in the run-length encoding state machine, which can enter an infinite loop during processing, effectively hanging the event-loop thread. This issue has been addressed and fixed in the specified versions.
Potential Impact
An attacker can cause a denial-of-service (DoS) by sending a specially crafted malformed bzip2 stream to a vulnerable Netty instance. This results in the event-loop thread entering an infinite loop, leading to resource exhaustion and service unavailability. There is no impact on confidentiality or integrity reported.
Mitigation Recommendations
Upgrade Netty to version 4.1.136.Final or later, or 4.2.16.Final or later, where this vulnerability has been fixed. No other mitigations are specified or required.
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: 10/18/2026, 04:35:02 UTC
Last updated: 10/21/2026, 13:20:22 UTC
Views: 211
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