CVE-2026-20579 in MT2718
Summary
by MITRE • 10/05/2026
In vdec, there is a possible out of bounds write due to type confusion. This could lead to local escalation of privilege if a malicious actor has already obtained the System privilege. User interaction is not needed for exploitation. Patch ID: ALPS11383899; Issue ID: MSV-9800.
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Analysis
by VulDB Data Team • 10/05/2026
The vulnerability identified under issue identifier MSV-9800 and addressed by patch ALPS11383899 resides within the vdec component, which is typically responsible for video decoding operations in embedded or mobile systems. This specific flaw manifests as an out-of-bounds write condition resulting from a type confusion error. Type confusion vulnerabilities occur when software incorrectly interprets data of one type as another, leading to unexpected behavior during memory access operations. In this context, the vdec module likely fails to properly validate or cast input parameters before performing memory writes, allowing a crafted payload to overwrite adjacent memory locations that are not intended for modification by the decoding routine.
From a technical perspective, out-of-bounds write vulnerabilities represent a critical class of memory safety issues categorized under CWE-787 in the Common Weakness Enumeration framework. The core mechanism involves writing data beyond the allocated boundaries of a buffer or object structure due to improper type handling. When an attacker can control the input that triggers this path within vdec, they may be able to corrupt heap metadata, overwrite function pointers, or modify critical system structures located adjacent to the target memory region. This corruption serves as the foundational step for achieving arbitrary code execution or altering program flow in a manner beneficial to the attacker.
The operational impact of this vulnerability is significant because it facilitates local privilege escalation. The description explicitly notes that exploitation requires the malicious actor to have already obtained System privileges, which implies that this flaw likely exists within a component running at a high integrity level or serves as an additional elevation vector for processes that have achieved elevated status through other means. While user interaction is not required for exploitation, meaning remote code execution via network services could potentially trigger it if the service runs with sufficient rights, the primary risk profile centers on lateral movement and persistence within a compromised system where initial access has already been established by an adversary operating at or near the highest privilege tier available to them.
This vulnerability aligns with several tactics in the MITRE ATT&CK framework, particularly those related to Defense Evasion and Privilege Escalation. The use of type confusion to achieve memory corruption is a common technique observed in advanced persistent threats seeking to bypass security controls such as Address Space Layout Randomization or Data Execution Prevention by manipulating control flow data structures like vtables or exception handling records. By exploiting this flaw, an attacker could potentially disable further security mechanisms installed on the device, thereby maintaining long-term access and expanding their influence over the system environment without detection from standard monitoring tools that rely on predictable execution paths.
Mitigation strategies for this vulnerability primarily involve applying the vendor-provided patch ALPS11383899 to update the vdec component with corrected memory management logic. Developers should ensure that all type casts are validated against expected data structures and bounds checks are enforced before any write operations occur. For system administrators, it is crucial to maintain strict access controls even for services running at high privilege levels, adhering to the principle of least privilege where possible. Additionally, deploying runtime application self-protection mechanisms or memory corruption detection tools can help identify attempts to exploit type confusion vulnerabilities in real-time, providing an additional layer of defense against exploitation while patch management processes are completed.