CVE-2023-20735 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: ALPS07645178.
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Analysis
by VulDB Data Team • 01/08/2025
The vulnerability identified as CVE-2023-20735 represents a critical out-of-bounds write flaw within the vcu component of a system architecture. This issue stems from the absence of proper bounds checking mechanisms during memory operations, creating a scenario where arbitrary data can be written beyond the allocated memory boundaries. The vulnerability specifically affects systems where the vcu module handles user-provided or system-generated data that undergoes memory manipulation without adequate validation of buffer limits. Such missing safeguards allow malicious actors to potentially overwrite adjacent memory locations with controlled data, leading to unpredictable system behavior and potential privilege escalation.
The technical exploitation of this vulnerability requires an attacker to leverage the absence of bounds checking in the vcu module's memory handling routines. When the system processes input data through the vcu component, the lack of validation allows for memory writes that extend beyond intended buffer boundaries. This flaw operates at a low system level where memory corruption can occur during routine operations, making it particularly dangerous as it can be triggered without requiring user interaction or specialized conditions. The vulnerability's design flaw manifests in the absence of proper input sanitization and memory boundary validation, which are fundamental security practices that should be implemented in all system components handling external data.
The operational impact of CVE-2023-20735 extends significantly beyond simple memory corruption, as it enables local privilege escalation to system execution privileges. This means that an attacker who can successfully exploit this vulnerability can elevate their privileges from standard user level to full system administrator rights, potentially gaining complete control over the affected system. The implications are severe as this escalation allows for unrestricted access to system resources, data exfiltration, persistence mechanisms, and the ability to compromise other system components. The vulnerability's potential for privilege escalation aligns with attack patterns documented in the MITRE ATT&CK framework under privilege escalation techniques, specifically targeting system-level access through memory corruption vulnerabilities.
The mitigation strategy for this vulnerability involves applying the patch identified by patch ID ALPS07645149, which addresses the missing bounds checking implementation in the vcu module. System administrators should prioritize the deployment of this patch across all affected systems, particularly those operating in environments where privilege escalation could lead to significant security breaches. Additionally, implementing comprehensive memory safety checks and bounds validation should be integrated into the development lifecycle for all system components, following established security practices that align with CWE-129, which specifically addresses insufficient bounds checking in input validation. Organizations should also consider implementing runtime protections such as address space layout randomization and stack canaries to further reduce the exploitability of similar vulnerabilities.
The presence of this vulnerability highlights the critical importance of memory safety in system security architectures. It demonstrates how fundamental flaws in basic memory management operations can create pathways for severe privilege escalation attacks, emphasizing the need for comprehensive security testing including fuzzing and memory analysis tools. The vulnerability's characteristics align with common patterns found in the industry where insufficient input validation and memory boundary checks lead to exploitable conditions that can be leveraged for system compromise. Security teams should conduct thorough vulnerability assessments to identify similar issues in other system components and ensure that all memory operations include proper bounds checking mechanisms as part of their security development lifecycle processes.