CVE-2026-93206 Linux CVE debrief

Who should care

System administrators, Linux kernel maintainers, and developers working with PCI devices should assess exposure and verify kernel versions. Affected operators, platform administrators, vulnerability management teams, and security teams should review the vulnerability and implement necessary mitigations.

Why it matters

CVE-2026-93206 allows unprivileged processes to read PCI config space, potentially exposing sensitive data and bypassing access restrictions. System administrators and Linux kernel maintainers should assess exposure, verify kernel versions, and apply updates.

• Unprivileged processes can read PCI config space
• Potential for sensitive data exposure
• Bypassing of access restrictions
• Need for kernel updates and config reviews

Technical summary

The Linux kernel vulnerability (CVE-2026-93206) arises from differing capability checks between procfs and sysfs interfaces for PCI config space access. The proc_bus_pci_read() function checks the credentials of the task calling read(), whereas pci_read_config() checks the credentials of the process that opened the file. This discrepancy allows a privileged process to open the config space file and pass the file descriptor to an unprivileged process, which can then read the entire config space through procfs.

Defensive priority

Medium

Recommended defensive actions

• Review and update Linux kernel configurations to ensure proper access controls for PCI config space
• Implement monitoring to detect potential exploitation attempts
• Restrict access to PCI config space files
• Verify and apply kernel updates
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its description and references to kernel commits that address the issue. The Linux kernel vulnerability (CVE-2026-93206) was addressed through specific commits, including de139a339395, 47970b1b2aa6, and ab0fa82b2df9, which modified how capability checks are performed for PCI config space access.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.