CVE-2026-74754 Linux CVE debrief

Who should care

Defenders responsible for Linux kernel-based systems, particularly those using SCSI, should assess their exposure to this vulnerability. This includes Linux kernel developers, system administrators, and security teams managing Linux-based infrastructure.

Why it matters

This vulnerability can lead to system instability and potential denial-of-service (DoS) attacks. Defenders should prioritize verifying the Linux kernel version and applying patches to mitigate this vulnerability.

• Runtime PM usage count underflow can lead to system instability
• Potential for denial-of-service (DoS) attacks
• Increased risk of system crashes or freezes

Technical summary

The Linux kernel vulnerability CVE-2026-74754 is caused by the incorrect handling of the shost->eh_noresume flag in the SCSI error handling path. This flag is used to prevent runtime PM operations during error handling. However, the current implementation checks this flag twice in one error handling iteration, leading to a potential race condition that can result in a runtime PM usage count underflow.

Defensive priority

Defenders should prioritize verifying the Linux kernel version and applying patches to mitigate this vulnerability. This involves assessing the Linux kernel versions in use, identifying those that are affected, and applying the necessary patches or updates.

Recommended defensive actions

• Verify Linux kernel versions and identify affected systems
• Apply patches or updates to fix the vulnerability
• Monitor system logs for potential exploitation attempts
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The vulnerability is caused by the incorrect handling of the shost->eh_noresume flag in the SCSI error handling path. This flag is used to prevent runtime PM operations during error handling. However, the current implementation checks this flag twice in one error handling iteration, leading to a potential race condition.

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.