Linux Kernel up to 6.9.6 privilege escalation

Summaryinfo

A vulnerability identified as problematic has been detected in Linux Kernel up to 6.9.6. This affects an unknown function. The manipulation leads to an unknown weakness. This vulnerability is documented as CVE-2024-40975. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.9.6 and classified as problematic. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: platform/x86: x86-android-tablets: Unregister devices in reverse order Not all subsystems support a device getting removed while there are still consumers of the device with a reference to the device. One example of this is the regulator subsystem. If a regulator gets unregistered while there are still drivers holding a reference a WARN() at drivers/regulator/core.c:5829 triggers, e.g.: WARNING: CPU: 1 PID: 1587 at drivers/regulator/core.c:5829 regulator_unregister Hardware name: Intel Corp. VALLEYVIEW C0 PLATFORM/BYT-T FFD8, BIOS BLADE_21.X64.0005.R00.1504101516 FFD8_X64_R_2015_04_10_1516 04/10/2015 RIP: 0010:regulator_unregister Call Trace: regulator_unregister devres_release_group i2c_device_remove device_release_driver_internal bus_remove_device device_del device_unregister x86_android_tablet_remove On the Lenovo Yoga Tablet 2 series the bq24190 charger chip also provides a 5V boost converter output for powering USB devices connected to the micro USB port, the bq24190-charger driver exports this as a Vbus regulator. On the 830 (8") and 1050 ("10") models this regulator is controlled by a platform_device and x86_android_tablet_remove() removes platform_device-s before i2c_clients so the consumer gets removed first. But on the 1380 (13") model there is a lc824206xa micro-USB switch connected over I2C and the extcon driver for that controls the regulator. The bq24190 i2c-client *must* be registered first, because that creates the regulator with the lc824206xa listed as its consumer. If the regulator has not been registered yet the lc824206xa driver will end up getting a dummy regulator. Since in this case both the regulator provider and consumer are I2C devices, the only way to ensure that the consumer is unregistered first is to unregister the I2C devices in reverse order of in which they were created. For consistency and to avoid similar problems in the future change x86_android_tablet_remove() to unregister all device types in reverse order.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2024-40975 since 07/12/2024. The exploitation is known to be difficult. Neither technical details nor an exploit are publicly available.

Upgrading to version 6.9.7 eliminates this vulnerability. Applying the patch f0c982853d66/3de0f2627ef8 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.9.0
• 6.9.1
• 6.9.2
• 6.9.3
• 6.9.4
• 6.9.5
• 6.9.6

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Discussion