Netty QUIC stateless reset token material exposed through header-visible connection IDs
CVE-2026-50009

4.8MEDIUM

Key Information:

Vendor

Netty

Status
Netty
Vendor
CVE Published:
12 June 2026

What is CVE-2026-50009?

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.

Affected Version(s)

netty >= 4.2.0.Final, < 4.2.15.Final

References

https://github.com/netty/netty/security/advisories/GHSA-c...
x_refsource_CONFIRM
https://github.com/netty/netty/releases/tag/netty-4.2.15....
x_refsource_MISC

CVSS V3.1

Score:
4.8
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
Low
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.