CVE-2026-58827 in Android
Summary
by MITRE • 11/02/2026
In multiple functions of dma-buf.c, there is a possible use after free due to a race condition. 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 • 11/02/2026
The vulnerability identified in the Linux kernel's dma-buf subsystem represents a critical security flaw rooted in improper synchronization mechanisms during memory management operations. Specifically, within multiple functions located in the dma-buf.c source file, there exists a race condition that can lead to a use-after-free scenario. This type of defect occurs when a program continues to use a pointer after the memory it points to has been freed and potentially reallocated for another purpose. In the context of kernel-space operations like those handled by dma-buf, which is responsible for sharing buffer objects between different drivers and subsystems such as graphics processing units and display controllers, maintaining strict ownership semantics and lifecycle management is paramount. The failure to properly synchronize access to these shared buffers allows a thread or process to interact with memory that has already been released back to the system allocator, creating an unpredictable state within the kernel's internal data structures.
From a technical perspective, this race condition typically arises when one execution path frees a dma-buf object while another concurrent path retains a reference to it and attempts to access its contents or metadata. Without adequate locking mechanisms such as mutexes, spinlocks, or atomic operations to serialize these conflicting accesses, the kernel may dereference a dangling pointer. This can result in reading stale data, writing corrupted information into arbitrary memory locations, or triggering a kernel panic due to invalid memory addresses. The complexity of dma-buf interactions across various subsystems exacerbates this issue, as different drivers may have varying assumptions about when buffers are valid and accessible. The lack of robust reference counting checks at critical junctures allows the race window to be exploited by malicious actors who can trigger these conditions through carefully crafted system calls or ioctl operations that manipulate buffer lifecycles rapidly.
The operational impact of this vulnerability is severe, primarily because it facilitates local privilege escalation with no additional execution privileges required from the attacker. Since dma-buf operates at a low level within the kernel and interacts directly with hardware drivers, exploiting this use-after-free condition can allow an unprivileged user to gain root-level access or modify critical kernel structures. This effectively bypasses standard security boundaries imposed by Linux capabilities and namespaces. Furthermore, because no user interaction is needed for exploitation beyond initiating the specific system calls that trigger the race condition, automated attack tools could potentially leverage this flaw without requiring social engineering or physical access to the machine once local shell access is obtained. The ability to execute arbitrary code in kernel space means an attacker can install rootkits, disable security modules like SELinux or AppArmor, and exfiltrate sensitive data with impunity.
This vulnerability aligns closely with Common Weakness Enumeration (CWE) identifiers such as CWE-416, which describes Use After Free, and potentially CWE-362 for Concurrent Execution using Shared Resource with Improper Synchronization. In terms of the MITRE ATT&CK framework, this flaw supports techniques related to Privilege Escalation on Linux systems, specifically those involving exploitation of kernel vulnerabilities or improper handling of shared resources. Attackers would likely utilize local privilege escalation tactics to move from a low-privileged user context to a high-privilege system account, leveraging the race condition as the primary vector for gaining control over the operating system's core components.
Mitigation strategies must focus on both immediate patching and long-term architectural improvements within the kernel codebase. The most effective remediation is applying vendor-provided security updates that address the specific synchronization issues in dma-buf.c, ensuring that all references to buffer objects are properly validated before access and that reference counts are managed atomically. Developers should implement strict locking protocols around critical sections where buffers are allocated, freed, or accessed concurrently. Additionally, employing static analysis tools and dynamic fuzzing techniques during development can help identify similar race conditions in other parts of the kernel memory management subsystems. System administrators should ensure their systems are updated with the latest stable kernels that include fixes for this specific dma-buf vulnerability to prevent potential exploitation by local attackers seeking elevated privileges.