CVE-2026-57968 in Windows
Summary
by MITRE • 07/14/2026
Buffer over-read in Windows Subsystem for Linux allows an authorized attacker to elevate privileges locally.
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Analysis
by VulDB Data Team • 07/15/2026
The vulnerability under examination represents a critical buffer over-read condition within the Windows Subsystem for Linux WslApi.dll component that enables local privilege escalation for authenticated attackers. This flaw exists in the subsystem's application programming interface implementation where insufficient input validation and memory boundary checking allows malicious code execution to read beyond allocated buffer boundaries. The vulnerability manifests when the WslApi.dll processes certain API calls from Windows applications attempting to interact with Linux subsystem components, creating an opportunity for attackers to exploit memory access violations that could lead to arbitrary code execution with elevated privileges.
The technical implementation of this vulnerability stems from improper handling of string parameters within the WSL API interface where character buffer boundaries are not adequately validated before processing. Attackers can construct malicious input sequences that cause the subsystem to read memory locations beyond intended buffer limits, potentially exposing sensitive kernel memory regions or triggering information disclosure vulnerabilities that could be leveraged for privilege escalation. This over-read condition occurs in the context of Windows Subsystem for Linux where the WSL API serves as a bridge between Windows user mode processes and underlying Linux kernel components, creating a unique attack surface that combines both operating system layers.
The operational impact of this vulnerability extends beyond simple memory corruption as it creates a pathway for local privilege escalation from standard user accounts to SYSTEM level privileges within the Windows environment. The attacker must first establish a foothold within the WSL subsystem environment and then exploit the buffer over-read condition through carefully crafted API calls that trigger the memory access violation. This exploitation requires the attacker to have already established a valid user session and access to execute code within the WSL context, making it a local privilege escalation vulnerability rather than a remote attack vector. The vulnerability aligns with CWE-121 which describes stack-based buffer overflow conditions and demonstrates how improper bounds checking can create exploitable memory access patterns.
Mitigation strategies for this vulnerability should focus on both immediate patching and operational security enhancements. Microsoft has released security updates addressing the specific WSL API implementation flaw, requiring administrators to apply the latest cumulative updates to prevent exploitation attempts. Organizations should implement least privilege principles by restricting user access to WSL functionality where possible, as unauthorized access to WSL components significantly reduces attack surface exposure. Security monitoring should include detection of unusual API call patterns targeting the WSL subsystem and anomalous memory access behaviors that could indicate exploitation attempts. The vulnerability relates to ATT&CK technique T1068 which covers local privilege escalation through system binary manipulation and demonstrates how legitimate system interfaces can be abused when proper input validation is absent.
The broader implications of this vulnerability highlight the complexity of modern operating system integration where cross-platform components create unique security challenges that differ from traditional monolithic systems. The WSL subsystem design introduces additional attack vectors that must be considered in security assessments, particularly when evaluating the trust boundaries between Windows and Linux execution environments. Organizations should conduct comprehensive security reviews of all subsystem interfaces and implement robust input validation controls to prevent similar buffer over-read conditions in other components. Regular vulnerability assessments targeting API interfaces and memory handling routines can help identify potential issues before exploitation occurs, emphasizing the importance of proactive security measures in complex hybrid computing environments that combine multiple operating system technologies.