CVE-2023-20643 in MT6739
Summary
by MITRE • 03/07/2023
In ril, 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: ALPS07628584; Issue ID: ALPS07628584.
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Analysis
by VulDB Data Team • 08/28/2025
The vulnerability identified as CVE-2023-20643 resides within the ril component of Android systems, representing a critical out-of-bounds write flaw that undermines system security integrity. This issue manifests as a missing bounds check during memory operations, creating a pathway for malicious code execution that could result in privilege escalation. The vulnerability specifically affects systems where the ril service operates, which handles radio interface layer communications between the Android framework and cellular hardware components. The absence of proper input validation in this critical system component creates an exploitable condition that adversaries can leverage without requiring user interaction, making it particularly dangerous in mobile environments where system-level access can lead to comprehensive device compromise.
The technical nature of this vulnerability aligns with CWE-787, which describes out-of-bounds write conditions that occur when code attempts to write data beyond the boundaries of a fixed-length buffer. In the context of ril operations, this typically involves telecommunications protocol processing where incoming radio data packets are handled without adequate boundary verification. The flaw allows attackers to overwrite adjacent memory locations, potentially corrupting critical system structures or injecting malicious code that can execute with system-level privileges. This memory corruption can manifest through various attack vectors including malformed SMS messages, cellular protocol anomalies, or crafted network communications that trigger the vulnerable code path within the ril service.
The operational impact of CVE-2023-20643 extends beyond simple privilege escalation to encompass potential full system compromise and data exfiltration capabilities. When exploited successfully, this vulnerability enables attackers to gain system execution privileges without user interaction, effectively bypassing standard Android security models that rely on user consent for dangerous operations. The implications are particularly severe in enterprise environments where mobile devices handle sensitive corporate data, as successful exploitation could lead to complete device takeover and access to encrypted corporate resources. The vulnerability's location within the radio interface layer makes it especially concerning since it operates at a low system level where traditional security measures may be less effective, and the patch ID ALPS07628584 indicates this affects specific Android versions and device implementations from the Android Level 2023.
Mitigation strategies for CVE-2023-20643 primarily focus on applying the vendor-provided patch identified by ALPS07628584, which addresses the missing bounds check in the ril component through proper input validation and memory boundary enforcement. System administrators should prioritize immediate deployment of security updates across all affected devices, particularly those handling sensitive communications or operating in high-risk environments. Additional protective measures include implementing network-based monitoring for suspicious cellular traffic patterns that might indicate exploitation attempts, as well as maintaining comprehensive device inventory tracking to ensure all vulnerable systems receive patches promptly. Organizations should also consider implementing mobile device management solutions that can automatically enforce security updates and monitor for potential exploitation attempts through behavioral analysis of cellular protocol handling within the device's operating system. The vulnerability demonstrates the critical importance of secure coding practices in system-level components and reinforces the need for continuous security assessment of low-level system services that operate with elevated privileges.