CVE-2023-20738 in MT5696
Summary
by MITRE • 06/06/2023
In vcu, 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 not needed for exploitation. Patch ID: ALPS07645149; Issue ID: ALPS07645173.
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Analysis
by VulDB Data Team • 01/08/2025
The vulnerability identified as CVE-2023-20738 resides within the vcu component of a system, representing a critical out-of-bounds write flaw that stems from an absence of proper bounds checking mechanisms. This vulnerability manifests in a manner that allows for local privilege escalation, potentially enabling an attacker with system execution privileges to elevate their access level within the operating environment. The flaw specifically affects the vcu subsystem where memory operations occur without adequate validation of array indices or buffer boundaries, creating a scenario where malicious code can overwrite adjacent memory locations beyond the intended allocation. The absence of bounds checking represents a fundamental security weakness that directly violates secure coding practices and can result in unpredictable behavior including system crashes, data corruption, or unauthorized privilege escalation.
The technical nature of this vulnerability places it squarely within the scope of CWE-129, which addresses insufficient bounds checking, and more specifically aligns with CWE-787, representing out-of-bounds write conditions. The flaw operates at the kernel or system-level where memory management occurs, making it particularly dangerous as it can be exploited to gain elevated privileges without requiring user interaction or additional attack vectors. The vulnerability's exploitation pathway involves manipulating memory operations within the vcu subsystem to trigger memory corruption that can be leveraged for privilege escalation. The patch identifier ALPS07645149 and issue identifier ALPS07645173 suggest this vulnerability was addressed within a specific software release or firmware update, indicating that the flaw was likely discovered through systematic code review or automated vulnerability scanning processes.
From an operational perspective, this vulnerability presents a significant risk to system integrity and security posture as it enables local privilege escalation without user interaction, meaning that any process running with system execution privileges could potentially exploit this flaw. The impact extends beyond simple privilege elevation to encompass potential system compromise, data theft, or persistent access mechanisms that could be leveraged for further attacks. The vulnerability's characteristics align with ATT&CK technique T1068, which covers 'Exploitation for Privilege Escalation', and T1059, covering 'Command and Scripting Interpreter', as attackers could potentially use the elevated privileges to execute additional malicious commands or establish persistence within the compromised system.
Mitigation strategies for CVE-2023-20738 should prioritize immediate patch application as provided through the ALPS07645149 update, ensuring that all affected systems receive the necessary security fixes. Organizations should conduct comprehensive vulnerability assessments to identify all instances of the vulnerable vcu component and verify that the patch has been successfully applied. Additional defensive measures include implementing memory protection mechanisms such as stack canaries, address space layout randomization, and data execution prevention to make exploitation more difficult even if the underlying vulnerability remains unpatched. System monitoring should be enhanced to detect anomalous memory access patterns or privilege escalation attempts that could indicate exploitation attempts. Security teams should also consider implementing principle of least privilege controls and regular system integrity checks to reduce the attack surface and detect potential compromise indicators. The vulnerability demonstrates the critical importance of bounds checking in system-level code and underscores the necessity of thorough code review processes, particularly for memory management operations that handle user or system input data.