CVE-2021-0902 in MT6873
Summary
by MITRE • 12/17/2021
In apusys, there is a possible out of bounds read due to an incorrect bounds check. This could lead to local information disclosure with System execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS05672107; Issue ID: ALPS05656484.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 12/24/2021
The vulnerability identified as CVE-2021-0902 resides within the apusys component of a mobile operating system platform, specifically manifesting as an out-of-bounds read condition that stems from inadequate bounds checking mechanisms. This flaw represents a critical security weakness that allows an attacker to access memory locations beyond the intended buffer boundaries, potentially exposing sensitive system information. The vulnerability affects systems where apusys is implemented and requires system-level execution privileges for exploitation, indicating that an attacker must already possess elevated access rights to leverage this weakness effectively. The absence of user interaction requirements for exploitation makes this vulnerability particularly concerning as it can be triggered automatically without any direct user involvement or deception tactics.
The technical implementation of this vulnerability demonstrates a classic buffer overflow scenario where the bounds checking logic fails to properly validate memory access boundaries. This improper validation allows the system to read memory locations that should remain protected or inaccessible, potentially exposing confidential data such as cryptographic keys, user credentials, or system configuration details. The flaw specifically impacts the apusys module which typically handles system-level operations and resource management, making the information disclosure particularly severe given the privileged nature of the component. According to CWE classification, this vulnerability maps to CWE-129: Improper Validation of Array Index, which encompasses issues where array indices are not properly validated before use, leading to out-of-bounds memory access.
From an operational standpoint, this vulnerability creates significant risks for system security and data integrity. The local information disclosure capability means that an attacker with system execution privileges can extract sensitive data from memory regions that should remain protected. This information exposure could potentially lead to further exploitation opportunities, including privilege escalation attacks or the acquisition of credentials that might enable broader system compromise. The requirement for system execution privileges suggests that this vulnerability likely affects scenarios where malicious code has already gained root or administrative access to the system, potentially through other attack vectors or vulnerabilities. The patch ID ALPS05672107 and issue ID ALPS05656484 indicate that this vulnerability was addressed through a specific system update targeting the apusys component.
The mitigation strategies for CVE-2021-0902 primarily focus on implementing proper bounds checking mechanisms within the apusys module and ensuring that all memory access operations validate array indices before execution. System administrators should prioritize applying the vendor-provided patch ALPS05672107 to address the vulnerability comprehensively. Additionally, implementing robust input validation procedures and conducting regular security audits of system components can help prevent similar issues from occurring in other modules. From an ATT&CK framework perspective, this vulnerability aligns with techniques involving privilege escalation and credential access, as the information disclosure could provide attackers with data needed to advance their compromise. Organizations should also consider implementing monitoring solutions to detect anomalous memory access patterns that might indicate exploitation attempts. The vulnerability demonstrates the importance of rigorous code review processes and static analysis tools to identify potential buffer overflow conditions before they can be exploited in production environments.