CVE-2026-100659
Description
A flaw was found in the Netty HTTP/3 codec. This vulnerability allows access control and request routing bypasses due to missing validation of destination headers. A remote, unauthenticated attacker can exploit this flaw by sending a Hypertext Transfer Protocol (HTTP) request containing conflicting authority and host header values. If intermediary proxies and backend servers consult different headers, unauthorized requests may circumvent security boundaries to reach restricted resources.
Statement
odh-th-torch-cpu-py312-rhel9 and odh-th-torch-cuda-py312-rhel9 are not affected because default entry is start-notebook.sh and not a Netty HTTP/3 server. There is no HTTP/3 / netty-codec-http3 usage in the image build path.
Similarly openvsx-rhel9 uses spring-boot-starter-jetty and pins Netty only as a transitive version. There is no netty-codec-http3 usage in server code. And pluginregistry-rhel9 embeds that Open VSX server behind httpd.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.5 | N/A | 6.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | Low | N/A | Low |
| Integrity Impact | Low | N/A | Low |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Understanding the Weakness (CWE)
Integrity,Non-Repudiation,Access Control
Technical Impact: Unexpected State; Hide Activities; Bypass Protection Mechanism
An attacker could create HTTP messages to exploit a number of weaknesses including 1) the message can trick the web server to associate a URL with another URL's webpage and caching the contents of the webpage (web cache poisoning attack), 2) the message can be structured to bypass the firewall protection mechanisms and gain unauthorized access to a web application, and 3) the message can invoke a script or a page that returns client credentials (similar to a Cross Site Scripting attack).
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
