CVE-2022-20070 in MT6731
Summary
by MITRE • 04/12/2022
In ssmr, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege with System execution privileges needed. User interaction is no needed for exploitation. Patch ID: ALPS06362920; Issue ID: ALPS06362920.
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Analysis
by VulDB Data Team • 04/17/2022
The vulnerability identified as CVE-2022-20070 resides within the ssmr component, a system module that handles specific operational functions within the Android operating system. This flaw represents a critical security weakness that manifests as an out-of-bounds write condition, occurring when the system fails to validate array boundaries during memory operations. The vulnerability is classified under CWE-787, which specifically addresses out-of-bounds write conditions that can result in arbitrary code execution and privilege escalation. The ssmr module operates with elevated system privileges, making this vulnerability particularly dangerous as it provides a direct pathway for attackers to gain unauthorized access to system-level operations.
The technical implementation of this vulnerability stems from the absence of proper bounds checking within memory allocation and manipulation routines. When the ssmr component processes certain input data structures, it fails to verify that array indices remain within valid memory boundaries before performing write operations. This oversight allows malicious actors to craft specially formatted inputs that can overwrite adjacent memory locations, potentially corrupting critical system data structures or injecting malicious code into the execution flow. The vulnerability requires system execution privileges to exploit, indicating that it operates at a kernel or system-level context where such privileges are already available.
The operational impact of CVE-2022-20070 extends beyond simple memory corruption, as it enables local privilege escalation to system-level privileges without requiring user interaction. This characteristic makes the vulnerability particularly dangerous in environments where system-level access is already compromised or when attackers can leverage other initial footholds to reach the ssmr component. The lack of user interaction requirement means that exploitation can occur automatically once the vulnerable system is running, making it an attractive target for automated attacks and malware. This vulnerability directly relates to the ATT&CK technique T1068, which covers 'Local Privilege Escalation' and represents a significant threat to system integrity and security posture.
Mitigation strategies for this vulnerability should prioritize the immediate application of the provided patch ALPS06362920, which addresses the missing bounds check in the ssmr component. System administrators should implement comprehensive monitoring to detect any anomalous memory access patterns that might indicate exploitation attempts. Additional protective measures include implementing memory protection mechanisms such as stack canaries, address space layout randomization, and code integrity checks to prevent successful exploitation attempts. Organizations should also conduct thorough vulnerability assessments to identify any other components that might share similar memory handling patterns, as the underlying architectural flaw could potentially exist in related modules. The vulnerability demonstrates the importance of rigorous input validation and bounds checking in system-level code, emphasizing that even minor oversights in memory management can result in severe security implications.