CVE-2021-0941 Explained : Impact and Mitigation

This article provides an overview of CVE-2021-0941, a security vulnerability found in Android's kernel, potentially leading to a local privilege escalation attack.

Understanding CVE-2021-0941

CVE-2021-0941 is a vulnerability discovered in the bpf_skb_change_head function of filter.c in Android kernel, allowing for a possible out-of-bounds read due to a use-after-free scenario. The exploitation of this vulnerability could result in a local escalation of privilege, requiring System execution privileges without the need for user interaction.

What is CVE-2021-0941?

The CVE-2021-0941 vulnerability in Android's kernel arises from an out-of-bounds read issue in the bpf_skb_change_head function. This flaw could be exploited to achieve local privilege escalation, demanding System execution privileges but no user interaction.

The Impact of CVE-2021-0941

The impact of CVE-2021-0941 is significant as it allows attackers to potentially escalate their privileges locally, compromising the security of the Android system without any user involvement.

Technical Details of CVE-2021-0941

CVE-2021-0941 affects Android's kernel, specifically in the bpf_skb_change_head function within filter.c. The vulnerability enables an out-of-bounds read leading to a use-after-free scenario.

Vulnerability Description

The vulnerability in bpf_skb_change_head could be exploited to trigger an out-of-bounds read operation, thus leading to a use-after-free condition, ultimately paving the way for local privilege escalation attacks.

Affected Systems and Versions

Affected systems include Android devices utilizing the Android kernel. Given the potential impact, users should be wary of this vulnerability and take necessary precautions.

Exploitation Mechanism

Exploiting CVE-2021-0941 requires knowledge of triggering the out-of-bounds read scenario in the bpf_skb_change_head function, ultimately leading to the use-after-free condition for privilege escalation.

Mitigation and Prevention

Addressing CVE-2021-0941 involves immediate steps to secure the affected systems and implementing long-term security measures to prevent similar vulnerabilities.

Immediate Steps to Take

Users should stay updated with security bulletins from Android, apply patches promptly, and follow best security practices to mitigate the risk of exploitation.

Long-Term Security Practices

To enhance overall security posture, users should consider deploying security updates consistently, adopting secure coding practices, and maintaining a proactive security stance.

Patching and Updates

Given the severity of CVE-2021-0941, timely patching of systems running the affected Android kernel is crucial to prevent potential exploitation and safeguard system integrity.