CVE-2026-93147 Linux Kernel CVE debrief

Who should care

Defenders responsible for Linux kernel systems, particularly those in environments where the Linux kernel is used, should assess exposure and prioritize patching. This includes operators, platform administrators, vulnerability management teams, and security teams who need to verify Linux kernel version and apply patches to address this vulnerability.

Why it matters

CVE-2026-93147 is a Linux kernel vulnerability that requires verification and patching to prevent potential issues. Defenders should prioritize patching and monitoring.

• Potential for unintended behavior or crashes due to improper register loading
• Need for verification of Linux kernel version and patch application
• Importance of monitoring for potential exploitation attempts

Technical summary

The Linux kernel vulnerability, CVE-2026-93147, involves the loading of a 32-bit cpu_nr value into a 64-bit BPF_REG_0 register without proper zeroing of the upper bits. This has been addressed by replacing the ly instruction with llgf in s390/bpf. The vulnerability affects Linux kernel systems, particularly those in environments where the Linux kernel is used. Defenders should assess exposure and prioritize patching. The vulnerability has been resolved, and defenders should verify the Linux kernel version and apply patches to address this vulnerability.

Defensive priority

Defenders should prioritize verifying the Linux kernel version and applying patches to address this vulnerability, particularly in environments where the Linux kernel is used.

Recommended defensive actions

• Verify Linux kernel version and apply patches
• Review and update affected systems
• Monitor for potential exploitation attempts
• 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
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record and NVD vulnerability detail page provide information on this vulnerability, including its CVSS score and severity. Two source references are provided, detailing the specific code changes made to address the issue.

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.