CVE-2026-98517 Linux CVE debrief

Who should care

Linux kernel maintainers, Nouveau driver users, and system administrators should assess exposure and prioritize verification of affected systems. The vulnerability can cause a KASAN: slab-use-after-free Read report, leading to potential security risks. Affected operator, platform, vulnerability-management, and security-team impact should be carefully evaluated.

Why it matters

A use-after-free vulnerability in the Linux kernel's Nouveau driver can cause a KASAN: slab-use-after-free Read report. Linux kernel maintainers and users should assess exposure and prioritize verification of affected systems.

• Verify buffer object management in Nouveau driver
• Assess exposure of Linux kernel systems using Nouveau driver

Technical summary

The vulnerability occurs in the `nouveau_uvmm_sm` function when a buffer object (BO) is left in the TTM_PL_SYSTEM state. This causes a KASAN: slab-use-after-free Read report when the function is called. The issue is related to the Nouveau driver's management of buffer objects, and a detailed analysis of the vulnerability is necessary to understand its implications. The vulnerability can be triggered when the `nouveau_uvmm_sm` function is called, leading to a KASAN: slab-use-after-free Read report. Linux kernel maintainers and users should assess exposure and prioritize verification of affected systems.

Defensive priority

Linux kernel maintainers and users should assess exposure and prioritize verification of affected systems.

Recommended defensive actions

• Review Linux kernel logs for KASAN: slab-use-after-free Read reports
• Verify Nouveau driver configuration and buffer object management
• Update to the latest Linux kernel version if possible
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• 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

Evidence notes

The vulnerability was reported in the Linux kernel and is related to the Nouveau driver. The issue occurs when a buffer object is left in the TTM_PL_SYSTEM state, causing a use-after-free error. This vulnerability can be triggered when the `nouveau_uvmm_sm` function is called, leading to a KASAN: slab-use-after-free Read report. To verify the vulnerability, defenders should review the Linux kernel logs for KASAN: slab-use-after-free Read reports and assess the configuration of the Nouveau driver.

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.