CVE-2026-93206

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

PCI/proc: Use file_ns_capable() when checking config space read access

proc_bus_pci_read() decides how much of the config space is readable based

on capable(CAP_SYS_ADMIN), which checks the credentials of the task calling

read(), not the credentials of the process that opened the file.

The sysfs equivalent, pci_read_config(), has checked the credentials of the

opening process since commit de139a339395 ("pci: check caps from sysfs file

open to read device dependent config space"), so a privileged process can

open the config space file and pass the file descriptor to an unprivileged

process (for example, a process running a KVM guest with an assigned

device), which can then read the entire config space. The check was

subsequently routed through the LSM framework in commit 47970b1b2aa6 ("pci:

use security_capable() when checking capablities during config space read")

and converted to the dedicated helper in commit ab0

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References