CVE-2026-58747 in Android
Summary
by MITRE • 09/15/2026
In smmu_detach_dev of arm-smmu-v3.c, there is a possible permission bypass due to a logic error in the code. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.
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Analysis
by VulDB Data Team • 09/16/2026
The vulnerability identified within the Linux kernel's ARM SMMU v3 driver represents a critical security flaw rooted in improper access control mechanisms during device detachment operations. Specifically, the issue resides in the smmu_detach_dev function found in arm-smmu-v3.c. This component is responsible for managing the relationship between I/O devices and their corresponding Stream IDs within the System Memory Management Unit architecture. When a device is detached from an SMMU domain, the kernel must ensure that all translation contexts are properly invalidated and that no residual permissions allow unauthorized memory access or execution. The logic error in this routine fails to adequately enforce these constraints, creating a gap where permission checks are either skipped or incorrectly evaluated during the teardown process.
This logical flaw results in a potential bypass of security restrictions designed to isolate devices from system resources. In the context of ARM architecture, the SMMU acts as an IOMMU, providing hardware-level memory protection and isolation for peripheral devices. By failing to correctly clear or restrict permissions associated with detached devices, the vulnerability allows for unauthorized access to physical memory regions that should be inaccessible. This misconfiguration effectively undermines the virtualization and security boundaries established by the kernel's device management subsystems. The absence of rigorous validation during this specific phase means that malicious actors can exploit the window between detachment and final cleanup to retain elevated privileges or access sensitive data structures.
The operational impact of this vulnerability is severe, primarily due to its potential for local privilege escalation. An attacker who has gained initial foothold on the system, even with limited user-level permissions, could leverage this flaw to escalate their rights to those of the kernel or root level. The requirement for System execution privileges indicates that successful exploitation allows the adversary to execute arbitrary code within the most privileged context available on the operating system. This capability enables full control over the host machine, including the ability to install malware, exfiltrate confidential data, and modify security policies without detection. Since user interaction is not required for exploitation, the attack vector is fully remote or local but automated, significantly increasing the risk of compromise in environments where untrusted code execution might occur through other vectors such as web applications or compromised services.
From a classification perspective, this vulnerability aligns with CWE-269, which denotes Improper Privilege Management, specifically regarding the failure to enforce required privileges during state transitions like device detachment. It also relates to CWE-862, Missing Authorization, as the system fails to verify proper access rights before allowing operations that affect security boundaries. In terms of offensive tactics, this flaw supports techniques associated with MITRE ATT&CK ID T1055, Process Injection, or more broadly T1068 Exploitation for Privilege Escalation, where an attacker leverages a software vulnerability to gain higher-level access on the target system. The lack of user interaction further classifies it under automated exploitation scenarios often seen in worm-like propagation or persistent backdoor installation strategies.
Mitigation and remediation efforts must focus on patching the underlying kernel code to ensure that smmu_detach_dev performs comprehensive validation before releasing resources. Developers should implement strict checks to verify that all stream IDs are properly invalidated and that no residual mappings remain active after detachment. Additionally, enabling Kernel Hardening features such as KASLR and stack canaries can reduce the likelihood of successful exploitation by making memory layout unpredictable and detecting buffer overflows or control flow hijacks. System administrators should prioritize applying security updates to affected kernel versions immediately. Regular auditing of device driver code for similar logic errors in resource management routines is also recommended to prevent recurrence of such privilege escalation vulnerabilities across other subsystems within the operating system architecture.