CVE-2026-98871 Linux CVE debrief

Who should care

Defenders responsible for securing Linux kernel-based systems, particularly those utilizing the crypto: ccp functionality, should be aware of this vulnerability and take steps to verify and patch their systems.

Why it matters

A possible deadlock vulnerability was found in the Linux kernel's crypto: ccp - Fix possible deadlock in SEV init failure path. Defenders should prioritize verifying the Linux kernel version and applying patches to address this vulnerability, particularly for systems utilizing the crypto: ccp functionality.

• Potential deadlock in sev_do_cmd during cleanup path
• RMPUPDATE failure for pages after the first may cause issues
• Verification of Linux kernel version and patch application required

Technical summary

The __sev_platform_init_handle_init_ex_path() function calls rmp_mark_pages_firmware() with locked=false while the parent function of init_ex_path has already acquired the sev_cmd_mutex. This can result in a deadlock in sev_do_cmd during the cleanup path if an RMPUPDATE failure occurs for any page after the first. The vulnerability arises from the crypto: ccp functionality in the Linux kernel, affecting systems that utilize this functionality. Defenders should prioritize verifying the Linux kernel version and applying patches to address this vulnerability.

Defensive priority

Defenders should prioritize verifying the Linux kernel version and applying patches to address this vulnerability, particularly for systems utilizing the crypto: ccp functionality.

Recommended defensive actions

• Verify Linux kernel version and apply patches to address the vulnerability
• Review system configurations and ensure crypto: ccp functionality is properly secured
• Monitor system logs for potential deadlock occurrences
• Perform vulnerability assessment to identify potential exposure
• Implement compensating controls for exposed systems
• Track exceptions and retest remediated assets
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE record and source item provide details on the vulnerability, including its description and affected versions. However, the CVSS score and severity are not provided. Defenders should verify the Linux kernel version and apply patches to address this vulnerability, particularly for systems utilizing the crypto: ccp functionality. The vulnerability arises from the __sev_platform_init_handle_init_ex_path() function calling rmp_mark_pages_firmware() with locked=false while the parent function of init_ex_path has already acquired the

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.