CVE-2026-49743 in Graphics DDK
Summary
by MITRE • 07/24/2026
Software installed and run as a non-privileged user may conduct improper GPU system calls to manipulate the lifetimes of synchronisation objects in the kernel, leading to read/write UAFs.
During workload submission involving a fence exported by the GPU driver, the reference count of the underlying synchronisation primitive is not properly incremented. This can be exploited, by destroying the exported fence and prematurely release the underlying primitive, resulting in a potential use-after-free condition.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 07/24/2026
This vulnerability represents a critical kernel-level memory safety issue affecting GPU driver implementations where improper reference counting mechanisms create exploitable use-after-free conditions. The flaw occurs when software executing with non-privileged user permissions can manipulate GPU system calls to control the lifecycle of synchronization objects within kernel space. Specifically, during workload submission processes that involve fence objects exported by the GPU driver, the underlying synchronization primitive's reference count fails to be properly incremented upon export operations. This fundamental failure in reference counting creates a race condition where an attacker can prematurely destroy the exported fence object while the kernel still maintains references to the underlying synchronization primitive, leading to a scenario where freed memory can be accessed or modified by subsequent operations. The vulnerability directly maps to cwe-415 and cwe-416 within the common weakness enumeration framework, representing improper double-free conditions and use-after-free vulnerabilities respectively.
The operational impact of this vulnerability extends beyond simple memory corruption as it provides a pathway for privilege escalation and arbitrary code execution within kernel space. When the reference count is not properly managed during fence export operations, the synchronization primitive can be freed while still referenced by other components in the GPU driver subsystem, creating opportunities for attackers to manipulate kernel memory layouts and potentially execute malicious code with elevated privileges. This type of vulnerability aligns with attack techniques described in the attack pattern taxonomy under persistent threats that leverage kernel-level memory corruption vulnerabilities to gain system control. The exploitation requires minimal privileges but can lead to complete system compromise due to the kernel execution context.
Mitigation strategies for this vulnerability require comprehensive kernel-level fixes addressing the reference counting implementation during fence export operations. System administrators should ensure immediate patching of affected GPU drivers and kernel versions where this issue has been identified, as no reliable workarounds exist without modifying core driver behavior. The fix must enforce proper reference count management where every export operation increments the underlying synchronization primitive's reference count, ensuring that destruction only occurs when all references are properly released. Additionally, implementing kernel memory protection mechanisms such as slab allocation hardening and enhanced memory sanitization can help detect and prevent exploitation attempts. Regular security audits of GPU driver code should include thorough review of reference counting patterns and synchronization object lifetime management to identify similar issues in other subsystems. The vulnerability demonstrates the importance of proper resource management in kernel space and highlights the critical need for rigorous testing of driver code under various concurrent access scenarios.