CVE-2026-74290

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.

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.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.