CVE-2026-42587

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpContentDecompressor accepts a maxAllocation parameter to limit decompression buffer size and prevent decompression bomb attacks. This limit is correctly enforced for gzip and deflate encodings via ZlibDecoder, but is silently ignored when the content encoding is br (Brotli), zstd, or snappy. An attacker can bypass the configured decompression limit by sending a compressed payload with Content-Encoding: br instead of Content-Encoding: gzip, causing unbounded memory allocation and out-of-memory denial of service. The same vulnerability exists in DelegatingDecompressorFrameListener for HTTP/2 connections. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

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-f6hv-jmp6-3vwv	Exploit Mitigation Vendor Advisory
https://github.com/netty/netty/security/advisories/GHSA-f6hv-jmp6-3vwv	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

18 May 2026, 12:20

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-f6hv-jmp6-3vwv -~~	() https://github.com/netty/netty/security/advisories/GHSA-f6hv-jmp6-3vwv - Exploit, Mitigation, Vendor Advisory

13 May 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-13 19:17

Updated : 2026-05-18 12:20

NVD link : CVE-2026-42587

Mitre link : CVE-2026-42587

CVE.ORG link : CVE-2026-42587

JSON object : View

Products Affected

netty

netty

CWE

CWE-400

Uncontrolled Resource Consumption

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