CVE-2021-0875 : What You Need to Know

A missing size check in PVRSRVBridgeChangeSparseMem of the PowerVR kernel driver could lead to local privilege escalation in Android devices.

Understanding CVE-2021-0875

This CVE involves a vulnerability in the PowerVR kernel driver on Android devices, potentially allowing an attacker to gain escalated privileges without requiring additional execution permissions.

What is CVE-2021-0875?

CVE-2021-0875 highlights an integer overflow issue in the PowerVR kernel driver's PVRSRVBridgeChangeSparseMem function. This flaw could enable an attacker to access out-of-bounds heap memory, leading to a local privilege escalation attack on the affected Android systems.

The Impact of CVE-2021-0875

The impact of this CVE is significant as it could allow malicious actors to elevate their privileges on Android devices, potentially compromising the security and integrity of the system without the need for user interaction.

Technical Details of CVE-2021-0875

This section delves into the specific technical aspects of the CVE, including the vulnerability description, affected systems, and exploitation mechanism.

Vulnerability Description

The vulnerability arises from a missing size check in the PVRSRVBridgeChangeSparseMem function of the PowerVR kernel driver, leading to a potential integer overflow. This flaw enables attackers to access out-of-bounds heap memory, facilitating a local privilege escalation attack.

Affected Systems and Versions

The CVE impacts Android devices utilizing the PowerVR kernel driver, particularly those running the Android SoC version. Systems with this configuration are considered vulnerable to the privilege escalation exploit.

Exploitation Mechanism

To exploit CVE-2021-0875, threat actors could leverage the integer overflow in PVRSRVBridgeChangeSparseMem to gain unauthorized access to restricted heap memory areas. By manipulating the overflow, attackers can escalate their privileges within the Android system.

Mitigation and Prevention

Understanding how to mitigate and prevent CVE-2021-0875 is crucial for maintaining the security of Android devices and safeguarding against potential privilege escalation attacks.

Immediate Steps to Take

Users and administrators should prioritize applying security patches provided by Android to address the CVE-2021-0875 vulnerability. Promptly installing these updates can prevent malicious actors from exploiting the flaw to elevate privileges.

Long-Term Security Practices

Implementing robust security practices, such as regularly updating device firmware and employing security mechanisms like SELinux, can help fortify Android devices against privilege escalation vulnerabilities in the long term.

Patching and Updates

Staying informed about security bulletins and releases from Android, particularly those addressing kernel driver vulnerabilities like CVE-2021-0875, is essential. Timely application of patches and updates is key to reducing the risk of exploitation and enhancing overall device security.