CVE-2025-71274 Linux CVE debrief

Who should care

Linux kernel developers, Linux distribution maintainers, cybersecurity teams, and users of Linux-based systems should be aware of this vulnerability. They should assess their exposure, apply patches or mitigations, and monitor for potential exploitation attempts. Additionally, organizations using Linux-based systems should review their asset inventory and ensure that their security teams are informed about the potential risks associated with this vulnerability. This includes reviewing system logs for signs of exploitation and maintaining up-to-date vulnerability management processes. Linux kernel developers and maintainers should prioritize patching and backporting fixes to supported kernel versions. Users and administrators should follow vendor guidance and apply patches as soon as possible to prevent potential exploitation. This may involve coordinating with Linux distribution maintainers to ensure timely patch availability and application. The vulnerability's impact on operational security and potential for exploitation should be carefully evaluated by affected organizations to ensure appropriate risk management and mitigation strategies are implemented. This includes considering compensating controls for exposed systems while remediation is scheduled and verified. Monitoring and detection capabilities should be reviewed to ensure they can identify potential exploitation attempts related to this vulnerability. Asset inventory management should be updated to reflect affected systems and track remediation progress. Rollback and change management processes should be prepared in case patch application requires system restarts or other changes that could impact operations. Source tracking and verification of patch application should be performed to confirm that all affected systems are properly mitigated. This vulnerability highlights the importance of maintaining up-to-date Linux kernel versions and having robust vulnerability management practices in place to address emerging threats effectively. By taking these steps, organizations can reduce their risk exposure and protect their Linux-based systems from potential attacks leveraging this vulnerability. Effective

Technical summary

The Linux kernel's rpmsg driver has a use-after-free vulnerability due to a race condition between the driver_override_show and driver_override_store functions. The show function reads the driver_override string without holding the device_lock, while the store function modifies and frees the string while holding the device_lock. To fix this, the rpmsg_string_attr macro has been replaced with explicit show and store functions.

Defensive priority

High

Recommended defensive actions

• Apply patches from Linux kernel maintainers
• Use the standard driver_set_override helper
• Hold device_lock during read operations
• Monitor Linux kernel updates for further patches
• 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 is caused by a race condition in the rpmsg driver. The driver_override_show function reads the driver_override string without holding the device_lock, while the driver_override_store function modifies and frees the string while holding the device_lock. To fix this, the rpmsg_string_attr macro has been replaced with explicit show and store functions. The new driver_override_store uses the standard driver_set_override helper. The new driver_override_show now correctly holds the device_lock during the read operation to prevent the race.

Official resources