CVE-2026-55831 Security Details

CVE ID

CVE-2026-55831

CWE

CWE-400

CWE-770

CVE Description

Netty is a network application framework for development of protocol servers and clients. Prior to 4.1.136.Final and 4.2.16.Final, Netty's SPDY SETTINGS decoder accepts a peer-declared SETTINGS entry count up to the 24-bit frame-length limit and materializes every unique setting ID in `DefaultSpdySettingsFrame`, allowing a remote SPDY/3.1 peer to send a syntactically valid roughly 2 MiB SETTINGS frame that creates 262144 map entries and amplifies network input into heap growth and ordered-map insertion work. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

Published

Jul 21, 2026

CVSS Score & Severity

7.5High

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Score

0.439%

Malware

malware

KEV Status

Not in KEV Catalog: No known exploits

Affected Ecosystems

affected

Source

National Vulnerability Database

References

GitHub · netty/nettyPROJECT