CVE-2018-19939 : Exploit Details and Defense Strategies

In the Mi A2 Lite and RedMi6 pro devices, a vulnerability in the Goodix GT9xx touchscreen driver for customized Linux kernels has been identified, leading to a NULL pointer dereference issue.

Understanding CVE-2018-19939

This CVE entry highlights a specific vulnerability affecting certain Xiaomi devices due to a driver issue.

What is CVE-2018-19939?

The vulnerability involves a NULL pointer dereference in the Goodix GT9xx touchscreen driver on Xiaomi daisy-o-oss and daisy-p-oss devices.

The Impact of CVE-2018-19939

The vulnerability can be exploited to cause a denial of service (DoS) condition on the affected devices.

Technical Details of CVE-2018-19939

The technical aspects of the vulnerability are crucial for understanding its implications.

Vulnerability Description

The issue arises during the execution of kfree after a kmalloc failure in the gtp_read_Color function within the driver's code.

Affected Systems and Versions

Devices: Mi A2 Lite and RedMi6 pro
Driver: Goodix GT9xx touchscreen driver
Customized Linux Kernels: Xiaomi daisy-o-oss and daisy-p-oss

Exploitation Mechanism

The vulnerability is triggered by a specific sequence of actions that lead to a NULL pointer dereference, potentially causing system instability.

Mitigation and Prevention

Addressing the CVE-2018-19939 vulnerability requires immediate actions and long-term security measures.

Immediate Steps to Take

Monitor security advisories from Xiaomi for patches or workarounds.
Consider disabling the touchscreen driver temporarily if feasible.

Long-Term Security Practices

Regularly update device firmware to apply security patches.
Implement proper error handling mechanisms in drivers to prevent similar issues.

Patching and Updates

Apply patches provided by Xiaomi to fix the vulnerability.