CVE-2026-59899

Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, `HttpContentEncoder` (the superclass of the production handler `HttpContentCompressor`) maintains a per-channel `ArrayDeque<CharSequence>` named `acceptEncodingQueue` that accumulates attacker-controlled data without any size limit. The queue is filled on the I/O thread for every inbound HTTP request and drained only when the application later writes a non-1xx response. This creates a resource exhaustion vulnerability when an attacker exploits HTTP/1.1 pipelining to flood the connection with requests faster than the application produces responses. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.

CVSS

No CVSS.

References

Link	Resource
https://github.com/netty/netty/releases/tag/netty-4.1.136.Final
https://github.com/netty/netty/releases/tag/netty-4.2.16.Final
https://github.com/netty/netty/security/advisories/GHSA-q4f6-jm68-57ww

Configurations

No configuration.

History

29 Jul 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-29 18:16

Updated : 2026-07-30 16:33

NVD link : CVE-2026-59899

Mitre link : CVE-2026-59899

CVE.ORG link : CVE-2026-59899

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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