CVE-2026-64248 Linux CVE debrief

Who should care

Users of Linux kernel versions 6.1.175 to 6.1.178, 6.6.142 to 6.6.145, 6.12.92 to 6.12.95, 6.18.34 to 6.18.38, 7.0.11 to 7.1, and 7.1.1 to 7.1.3 should apply patches to prevent Linux kernel vulnerability. This includes operators, platform administrators, vulnerability management teams, and security teams who need to assess and mitigate this vulnerability in their environments. Affected product deployments should be identified and prioritized for patching based on risk and exposure. Compensating controls may be necessary for exposed systems while remediation is scheduled and verified. Monitoring and detection capabilities should be reviewed to ensure they can identify potential exploitation attempts. Asset inventory and rollback/change windows should also be considered in the remediation process. Source tracking can help verify the effectiveness of these measures. These actions can help minimize the risk associated with this vulnerability until patches can be applied. Vulnerability management processes should be updated to include checks for this CVE in the future. Security teams should track exceptions, retest remediated assets, and close the item only after evidence is documented. This process ensures that all necessary steps are taken to mitigate the vulnerability effectively. By taking these steps, organizations can reduce their exposure to potential attacks exploiting this vulnerability. It is essential to prioritize and expedite the application of patches or mitigations to minimize the risk of exploitation. This CVE highlights the importance of maintaining up-to-date Linux kernel versions and having robust vulnerability management practices in place. By doing so, organizations can better protect their systems and data from potential threats. The vulnerability management process should include regular reviews of CVE records and NVD details to ensure timely identification and mitigation of vulnerabilities like CVE-2026-64248. This proactive approach can help prevent similar issues in the future. In addition to patching, other defensive measures such as compensating controls, monitoring, and asset inventory can help mitigate the risk of this vulnerability. By

Technical summary

The Linux kernel vulnerability was resolved by reporting dying CPU to RCU in stop_this_cpu(). The issue was noticed on several Realtek MIPS switch SoCs and came up during kernel bump downstream in OpenWrt from 6.18.33 to 6.18.34. The patch also has been backported all the way back to 6.1. This vulnerability impacts Linux kernel versions 6.1.175 to 6.1.178, 6.6.142 to 6.6.145, 6.12.92 to 6.12.95, 6.18.34 to 6.18.38, 7.0.11 to 7.1, and 7.1.1 to 7.1.3.

Defensive priority

Apply patches to prevent Linux kernel vulnerability

Recommended defensive actions

• Apply patches to prevent Linux kernel vulnerability
• Inventory Linux kernel versions for potential updates
• Monitor Linux kernel for vulnerabilities
• 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 Linux kernel vulnerability was resolved by reporting dying CPU to RCU in stop_this_cpu(). The issue was noticed on several Realtek MIPS switch SoCs and came up during kernel bump downstream in OpenWrt from 6.18.33 to 6.18.34. The patch also has been backported all the way back to 6.1.

Official resources