CVE-2026-64347

Description

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: composite: fix dead empty check in the USB_DT_OTG handler The OTG branch of composite_setup() falls back to the first configuration when none is selected: if (cdev->config) config = cdev->config; else config = list_first_entry(&cdev->configs, struct usb_configuration, list); if (!config) goto done; ... memcpy(req->buf, config->descriptors[0], value); list_first_entry() never returns NULL. On an empty list it returns container_of() of the list head. So the "if (!config)" check is dead. When cdev->configs is empty, config points at the head inside struct usb_composite_dev. config->descriptors[0] reads whatever sits at that offset. The memcpy copies up to w_length bytes of it into the response buffer. cdev->configs can be empty in two cases. One is a teardown race on gadget unbind with a control transfer in flight. The other is a driver that sets is_otg before it adds a config. A reproducer that holds cdev->configs empty triggers a KASAN fault in this branch. Use list_first_entry_or_null() so the existing check does its job.

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EPSS — Exploit Prediction

0.0022

Probability of exploitation

0.13%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/01feaf024f29618d5ffa7ab0fd858e0579dcbf7b https://git.kernel.org/stable/c/2454264b2ab4cf0055c0bfd39e79f830452bd0db https://git.kernel.org/stable/c/56add2b9b2e89ec61c0761165d758f73004fdfdf https://git.kernel.org/stable/c/8ac463fe6c0f85bdb1ce8c30e8c9e060802e4483 https://git.kernel.org/stable/c/91b3ecd34b60f950c50c560974945b6596a6f207 https://git.kernel.org/stable/c/d3e72cfef2e38bd588055739a8100d14f9773b17 https://git.kernel.org/stable/c/f8f680609c2b3ab795ffcd6f21585b6dfc46d395 https://git.kernel.org/stable/c/fcb21bf747640c9d6bd1eda9da85420f076d59c1

Frequently Asked Questions

What is CVE-2026-64347? +

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: composite: fix dead empty check in the USB_DT_OTG handler The OTG branch of composite_setup() falls back to the first configuration when none is selected: if (cdev->config) config = cdev->config; else config = list_first_entry(&cdev->configs, struct usb_configuration, list); if (!config) goto done; ... memcpy(req->buf, config->descriptors[0], value); list_first_entry() never returns NULL. On an empty list it returns container_of() of the list head. So the "if (!config)" check is dead. When cdev->configs is empty, config points at the head inside struct usb_composite_dev. config->descriptors[0] reads whatever sits at that offset. The memcpy copies up to w_length bytes of it into the response buffer. cdev->configs can be empty in two cases. One is a teardown race on gadget unbind with a control transfer in flight. The other is a driver that sets is_otg before it adds a config. A reproducer that holds cdev->configs empty triggers a KASAN fault in this branch. Use list_first_entry_or_null() so the existing check does its job.

How do I check if I'm vulnerable to CVE-2026-64347? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.