CVE-2026-68088 in Linux
Summary
by MITRE • 08/10/2026
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: function: rndis: add length check to response query
Add variable representations for BufLength and BufOffset in rndis_query_response(), and perform a length check on them.
This is identical to how rndis_set_response() handles these parameters.
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Analysis
by VulDB Data Team • 08/10/2026
The vulnerability addressed in this linux kernel update represents a critical security flaw within the usb gadget framework's rndis function implementation. This issue affects the remote ndis protocol handler which is responsible for managing usb network connections between host and device systems. The vulnerability stems from inadequate input validation within the rndis_query_response() function, where buffer length and offset parameters are not properly verified before processing. This creates a potential avenue for attackers to exploit memory corruption vulnerabilities through malformed usb responses.
The technical flaw manifests in the missing validation of BufLength and BufOffset variables within the rndis_query_response() function. These parameters control buffer boundaries during response generation and are crucial for maintaining memory safety. Without proper length checking, malicious usb traffic could cause integer overflow conditions or buffer overruns that might lead to arbitrary code execution or system crashes. The vulnerability is particularly concerning because it operates at the kernel level where such flaws can result in complete system compromise.
The operational impact of this vulnerability extends beyond simple denial of service scenarios. Attackers with physical access to usb ports or those able to establish malicious usb connections could leverage this weakness to execute privileged code within the kernel space. This aligns with common attack patterns documented in the attack tree framework where usb-based attacks represent a significant threat vector for embedded systems and mobile devices. The vulnerability affects any system running linux kernel versions that include the affected rndis gadget implementation, making it a widespread concern for networked devices.
This security patch implements defensive programming practices by adding proper length validation for BufLength and BufOffset parameters in rndis_query_response() function. The fix mirrors the existing pattern already established in rndis_set_response() which demonstrates adherence to secure coding standards and best practices within kernel development. The solution follows principles from common weakness enumeration cwes such as cwe-129 input validation and cwe-787 out of bounds read/write conditions.
The mitigation approach taken by this patch exemplifies the principle of least privilege and defense in depth strategies recommended in cybersecurity frameworks. By implementing proper boundary checking, the kernel prevents potential exploitation scenarios that could lead to privilege escalation or system compromise. This fix aligns with established security practices for usb gadget drivers and demonstrates how simple input validation can prevent complex exploitation chains. The solution also reinforces the importance of consistent security implementation across similar functions within the same codebase.
The vulnerability resolution represents a typical case where kernel security updates address memory safety issues through proper parameter validation. This approach ensures that buffer operations remain within allocated memory boundaries while maintaining compatibility with legitimate usb network protocols. The fix maintains the expected functionality of rndis protocol handling while eliminating potential attack vectors that could be exploited by malicious actors in physical access scenarios or usb-based attacks targeting embedded systems and mobile platforms.