CVE-2026-44894
Netty's Default QUIC token handler accepts any client-supplied token
Description
Netty is a network application framework for development of protocol servers and clients. NoQuicTokenHandler is the tokenHandler used when the application does not set one. Prior to version 4.2.15.Final, its writeToken() returns false (server will not send Retry — acceptable), but validateToken() unconditionally `return 0`. In QuicheQuicServerCodec.handlePacket(), a non-negative return from validateToken() is interpreted as 'token is valid, ODCID starts at offset 0', causing the server to call quiche_accept as if the client's address had been validated by a Retry round-trip. Per RFC 9000 §8.1, a validated address lifts the 3× anti-amplification send limit. Thus any attacker who includes ANY non-empty token bytes in an Initial packet — with a spoofed victim source IP — causes the Netty server to treat the victim as validated and reflect full-size handshake flights (certificates, etc.) toward it without the 3× cap. The correct 'no token handler' semantics would be to return -1 (invalid) so the normal un-validated path and amplification limit apply. Version 4.2.15.Final patches the issue.
INFO
Published Date :
June 12, 2026, 3:16 p.m.
Last Modified :
July 15, 2026, 2:22 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c |
Solution
- Update Netty to version 4.2.15.Final or later.
- Verify token validation logic in NoQuicTokenHandler.
- Ensure validateToken() returns -1 for no token handler.
- Apply RFC 9000 §8.1 compliant address validation.
Public PoC/Exploit Available at Github
CVE-2026-44894 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-44894.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-44894 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-44894
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
None
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Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-44894 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-44894 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Jul. 15, 2026
Action Type Old Value New Value Changed Affected [{'cpes': ['cpe:/a:redhat:apache_camel_hawtio:4'], 'vendor': 'Red Hat', 'product': 'Red Hat build of Apache Camel - HawtIO 4', 'defaultStatus': 'affected'}] [{'cpes': ['cpe:/a:redhat:apache_camel_hawtio:4'], 'vendor': 'Red Hat', 'product': 'Red Hat build of Apache Camel - HawtIO 4', 'packageName': 'netty-codec-classes-quic', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}] -
CVE Modified by 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Jun. 30, 2026
Action Type Old Value New Value Added Affected [{'cpes': ['cpe:/a:redhat:apache_camel_hawtio:4'], 'vendor': 'Red Hat', 'product': 'Red Hat build of Apache Camel - HawtIO 4', 'defaultStatus': 'affected'}] Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-346 Added Reference https://access.redhat.com/security/cve/CVE-2026-44894 Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2488380 Added Reference https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44894.json -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'netty', 'product': 'netty', 'versions': [{'status': 'affected', 'version': '>= 4.2.0.Final, < 4.2.15.Final'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-44894', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-13T03:03:54.989814Z'} -
Initial Analysis by [email protected]
Jun. 15, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* versions from (including) 4.2.0 up to (excluding) 4.2.15 Added Reference Type GitHub, Inc.: https://github.com/netty/netty/releases/tag/netty-4.2.15.Final Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/netty/netty/security/advisories/GHSA-cmm3-54f8-px4j Types: Vendor Advisory -
New CVE Received by [email protected]
Jun. 12, 2026
Action Type Old Value New Value Added Description Netty is a network application framework for development of protocol servers and clients. NoQuicTokenHandler is the tokenHandler used when the application does not set one. Prior to version 4.2.15.Final, its writeToken() returns false (server will not send Retry — acceptable), but validateToken() unconditionally `return 0`. In QuicheQuicServerCodec.handlePacket(), a non-negative return from validateToken() is interpreted as 'token is valid, ODCID starts at offset 0', causing the server to call quiche_accept as if the client's address had been validated by a Retry round-trip. Per RFC 9000 §8.1, a validated address lifts the 3× anti-amplification send limit. Thus any attacker who includes ANY non-empty token bytes in an Initial packet — with a spoofed victim source IP — causes the Netty server to treat the victim as validated and reflect full-size handshake flights (certificates, etc.) toward it without the 3× cap. The correct 'no token handler' semantics would be to return -1 (invalid) so the normal un-validated path and amplification limit apply. Version 4.2.15.Final patches the issue. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Added CWE CWE-940 Added Reference https://github.com/netty/netty/releases/tag/netty-4.2.15.Final Added Reference https://github.com/netty/netty/security/advisories/GHSA-cmm3-54f8-px4j