CVE-2026-56945 in Android
Summary
by MITRE • 09/15/2026
In VPU, there is a possible out-of-bounds write due to a confused deputy. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability identified in the Video Processing Unit (VPU) represents a critical security flaw rooted in improper access control mechanisms, specifically categorized as a Confused Deputy problem. In this context, the VPU subsystem fails to adequately verify that it is acting on behalf of an authorized entity with sufficient privileges before performing sensitive operations. This architectural weakness allows lower-privileged processes or malicious actors to manipulate the VPU into executing actions intended for higher-privilege contexts. The core technical flaw lies in the failure to enforce strict identity verification and permission checks during command submission or buffer management, leading directly to a memory safety violation known as an out-of-bounds write.
An out-of-bounds write occurs when software writes data beyond the boundaries of allocated memory buffers. In the case of this VPU vulnerability, the confused deputy condition enables an attacker to craft specific inputs that cause the hardware or its driver interface to write data into unintended memory locations. This can overwrite adjacent memory structures such as function pointers, return addresses on the stack, or critical kernel data structures. Because the operation is performed by a privileged component like the VPU driver or firmware, the resulting corruption occurs within a high-privilege context, even if the initial trigger originated from an unprivileged user space application. This mechanism effectively bypasses standard memory protection boundaries that would normally prevent such writes in non-privileged contexts.
The operational impact of this vulnerability is severe due to its potential for local privilege escalation. An attacker who gains access to the system, whether through a compromised web browser, a malicious document viewer, or any other application with user-level permissions, can exploit this flaw without requiring additional execution privileges beyond what is already granted by their current session. Since no user interaction is needed for exploitation once the initial foothold is established, an automated attack vector exists that allows rapid compromise of the system integrity. The attacker can achieve arbitrary code execution in kernel space or with elevated hardware-level permissions, effectively taking full control over the device and potentially installing persistent malware, exfiltrating sensitive data, or pivoting to other systems on the network.
From a classification perspective, this vulnerability aligns closely with CWE-269 Improper Privilege Management, as it involves a failure to properly enforce privilege boundaries during operation execution. The confused deputy aspect is also indicative of CWE-841 Improper Enforcement of Behavioral Workflow, where the system fails to ensure that actions are performed by the correct authorized entity. In terms of attack tactics, this aligns with MITRE ATT&CK techniques related to Privilege Escalation via Exploitation of Local Vulnerabilities and potentially Command and Scripting Interpreter abuse if the memory corruption leads to code execution within a scripting environment managed by the system.
Mitigation strategies must address both immediate remediation and long-term architectural improvements. The primary defense is the deployment of vendor-provided patches that correct the access control logic within the VPU driver or firmware, ensuring that all operations are strictly validated against the caller's actual privileges rather than assuming elevated status based on context alone. Developers should implement rigorous input validation to ensure that buffer sizes and indices remain within allocated limits before any hardware commands are issued. Furthermore, enabling memory protection features such as Kernel Address Space Layout Randomization (KASLR), Data Execution Prevention (DEP), and Stack Canaries can mitigate the exploitation of out-of-bounds writes by making it significantly harder for attackers to predict target addresses or execute injected code. Regular security audits focusing on hardware-software interaction points are essential to identify similar confused deputy scenarios in other subsystems.