PT-2026-48916 · Netty · Netty

Published 2026-06-12 · Updated 2026-06-12 · CVE-2026-50560

Mitre

CVSS v4.0

6.9

Medium

Base vector

AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, Netty HTTP/2 max header size handling produces an attack similar to HTTP/2 Rapid Reset. There is a setting in the http2 specification called SETTINGS MAX HEADER LIST SIZE. When a client sends that setting to Netty, it appears that Netty will behave as follows: read the request; proxy the request to the origin; attempt to produce a response; and create an exception while writing the headers for the response. Functionally, this should be similar to the http2 reset attack, but with a different on-the-wire signature. Versions 4.1.135.Final and 4.2.15.Final patch the issue.

Fix

Allocation of Resources Without Limits

Weakness Enumeration

CWE-770

Related Identifiers

CVE-2026-50560

Affected Products

Netty

References · 5

• https://nvd.nist.gov/vuln/detail/CVE-2026-50560 · Security Note
• https://github.com/netty/netty/releases/tag/netty-4.1.135.Final · Note
• https://github.com/netty/netty/releases/tag/netty-4.2.15.Final · Note
• https://rfc-editor.org/rfc/rfc9113.html#name-defined-settings · Note
• https://github.com/netty/netty/security/advisories/GHSA-563q-j3cm-6jxm · Note