# CVE-2026-59901: Netty Bzip2Decoder: Infinite Loop in RLE State Machine Leads to Event-Loop Thread Hang

> CVE-2026-59901: Netty Bzip2Decoder: Infinite Loop in RLE State Machine Leads to Event-Loop Thread Hang. CVSS 7.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-59901
Last updated: 2026-08-06T20:29:27Z

- Published: 2026-07-29 17:48 UTC · Updated: 2026-08-06 20:29 UTC · Assigner: GitHub\_M
- CVSS: 7.5 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS: 0.46%, 40th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-835

## Description

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 vendors and products

- netty: netty

## Tracked companies

- [Confluence](https://rewindex.com/company/confluence.md)
- [Jira](https://rewindex.com/company/jira.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-59901)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-59901)
- [https://github.com/netty/netty/security/advisories/GHSA-558v-64gr-wgg4](https://github.com/netty/netty/security/advisories/GHSA-558v-64gr-wgg4)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-59901 · Markdown: https://rewindex.com/cve/CVE-2026-59901.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-59901 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:10:42.020Z