CVE-2026-74290
Description
A flaw was found in the Linux kernel's cls_flow module. A local user, by operating a traffic control (tc) classifier within a user or network namespace, could manipulate specific parameters. This manipulation allows the user to recover sensitive 32-bit folded kernel pointer values, leading to information disclosure.
Statement
This vulnerability is rated as having Moderate severity because an attacker must possess local access and the capability to manage network or user namespaces to manipulate classifier parameters and observe class statistics. The resulting disclosure of folded kernel pointers weakens Kernel Address Space Layout Randomization (KASLR), potentially assisting secondary exploitation rather than directly enabling unauthorized system compromise. Environments that restrict unprivileged user namespaces further limit the potential attack surface.
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 | 5.5 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
