Bug 2513346 (CVE-2026-68366)

Summary: CVE-2026-68366 kernel: usb: gadget: uvc: clamp SEND_RESPONSE length to the response buffer
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the USB Video Class (UVC) gadget driver in the Linux kernel. The uvc_send_response() function, which constructs UVC control responses, fails to properly restrict the length of data copied into a response buffer. A remote attacker, by sending a specially crafted USB control request, could cause an out-of-bounds read. This could lead to information disclosure or a denial of service (DoS) on the affected system.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-08-10 12:32:13 UTC 
In the Linux kernel, the following vulnerability has been resolved:

usb: gadget: uvc: clamp SEND_RESPONSE length to the response buffer

uvc_send_response() builds the UVC control response from a user-supplied
struct uvc_request_data:

	req->length = min_t(unsigned int, uvc->event_length, data->length);
	...
	memcpy(req->buf, data->data, req->length);

req->length is clamped to uvc->event_length, which is taken from the
host control request wLength (up to UVC_MAX_REQUEST_SIZE, 64), and to
data->length, which comes from the UVCIOC_SEND_RESPONSE ioctl and is
only checked for being negative.  The source buffer data->data is only
60 bytes, so a response with uvc->event_length and data->length both
greater than 60 makes memcpy() read past the end of data->data.

Clamp req->length to sizeof(data->data) as well.