GitHub Advisoryadvisory · Maven

GHSA-q4f6-jm68-57ww Netty: [HttpContentEncoder] Unbounded Per-Connection Queue Growth via HTTP/1.1 Pipelining Leads to Denial of Service

MEDIUM Published 2026-07-22 Modified 2026-07-22 Official page ↗
Aliases
CVE-2026-59899
Ecosystem
Maven
Packages
io.netty:netty-codec-http
Severity
Moderate
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Weaknesses
CWE-770
Reviewed
2026-07-22

Affected packages

• Maven io.netty:netty-codec-http: >= 4.2.0.Final, < 4.2.16.Final → fixed in 4.2.16.Final • Maven io.netty:netty-codec-http: < 4.1.136.Final → fixed in 4.1.136.Final

Description

Impact `HttpContentEncoder` (the superclass of the production handler `HttpContentCompressor`) maintains a per-channel `ArrayDeque` 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.

Related

Alias · CVE (1)

  • CVE-2026-59899 Netty is an asynchronous, event-driven network application framework. vulnerability

Weakness · CWE (1)

  • CWE-770 Allocation of Resources Without Limits or Throttling weakness

References