PT-2026-47603 · Netty · Netty

Published 2026-06-08 · Updated 2026-06-08 · CVE-2026-44892

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

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

Name of the Vulnerable Software and Affected Versions Netty (affected versions not specified)

Description The default configuration of the Http3ConnectionHandler in the Netty HTTP/3 codec does not enforce a maximum header size limit. When a peer does not specify HTTP3 SETTINGS MAX FIELD SECTION SIZE, the implementation uses an unbounded limit. This allows a malicious actor to send an excessive number of headers, leading to memory exhaustion and a Denial of Service via an OutOfMemoryError. This occurs because the default behavior follows RFC 9114, which specifies an unlimited default, unlike Netty's HTTP/1.1 and HTTP/2 implementations that enforce secure limits. The unbounded limit is passed into Http3FrameCodec#newFactory and stored as maxHeaderListSize within Http3FrameCodec.

Recommendations Configure the maximum header field section size via Http3Settings to replace the insecure default unbounded limit.

Fix

Resource Exhaustion

Weakness Enumeration

CWE-1188

CWE-400

Related Identifiers

CVE-2026-44892

GHSA-C2RX-5R8W-8XR2

Affected Products

Netty

References · 5

• https://osv.dev/vulnerability/GHSA-c2rx-5r8w-8xr2 · Vendor Advisory
• https://github.com/netty/netty · Note
• https://twitter.com/dailycve/status/2064106198949925274 · Twitter Post
• https://github.com/netty/netty/security/advisories/GHSA-c2rx-5r8w-8xr2 · Note
• https://github.com/netty/netty/releases/tag/netty-4.2.15.Final · Note