CVE-2026-33871

Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.132.Final and 4.2.10.Final, a remote user can trigger a Denial of Service (DoS) against a Netty HTTP/2 server by sending a flood of `CONTINUATION` frames. The server's lack of a limit on the number of `CONTINUATION` frames, combined with a bypass of existing size-based mitigations using zero-byte frames, allows an user to cause excessive CPU consumption with minimal bandwidth, rendering the server unresponsive. Versions 4.1.132.Final and 4.2.10.Final fix the issue.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/netty/netty/security/advisories/GHSA-w9fj-cfpg-grvv	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:netty:netty::::::::
	cpe:2.3:a:netty:netty::::::::

History

30 Mar 2026, 20:10

Type	Values Removed	Values Added
First Time		Netty netty Netty
CPE		cpe:2.3:a:netty:netty::::::::
References	~~() https://github.com/netty/netty/security/advisories/GHSA-w9fj-cfpg-grvv -~~	() https://github.com/netty/netty/security/advisories/GHSA-w9fj-cfpg-grvv - Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5

Information

Published : 2026-03-27 20:16

Updated : 2026-03-30 20:10

NVD link : CVE-2026-33871

Mitre link : CVE-2026-33871

CVE.ORG link : CVE-2026-33871

JSON object : View

Products Affected

netty

netty

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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