CVE-2026-50009

What it is

Netty is a network application framework for development of protocol servers and clients. Prior to version 4.2.15.Final, Netty QUIC exposes the stateless reset token on the network path when using the default HMAC-based connection-ID and stateless-reset-token generators. The reset token for the server's current source connection ID can be derived from bytes that appear as the connection ID in QUIC headers after a source-CID rotation. An on-path attacker observing the headers can use the token to perform a Denial of Service by sending a spoofed Stateless Reset packet. Version 4.2.15.Final patches the issue.

At a glance

Exploitability

Can be exploited over the network without logging in. Limited direct impact.

Exploit odds

0.2% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-06-12 16:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 10:57 UTC Last updatedMost recent change to the record

Details

Published

2026-06-12 16:16 UTC

Last modified

2026-06-17 10:57 UTC

Exploit probability

0.2% · EPSS, next 30 days

Weakness

CWE-200 · Information exposure

Record status

Analyzed

Affected

• Netty < 4.2.15

Attack profile CVSS 3.1 · 4.8

Attack vector

Network

Complexity

High

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

Low