CVE-2021-46906: In the Linux kernel, the following vulnerability has been resolved: HID: usbhid: fix info leak in hid_submit_ctrl In hid_submit_ctrl(), the way of c...

Description

In the Linux kernel, the following vulnerability has been resolved: HID: usbhid: fix info leak in hid_submit_ctrl In hid_submit_ctrl(), the way of calculating the report length doesn't take into account that report->size can be zero. When running the syzkaller reproducer, a report of size 0 causes hid_submit_ctrl) to calculate transfer_buffer_length as 16384. When this urb is passed to the usb core layer, KMSAN reports an info leak of 16384 bytes. To fix this, first modify hid_report_len() to account for the zero report size case by using DIV_ROUND_UP for the division. Then, call it from hid_submit_ctrl().

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

0.25%

15.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-668

Affected Software

Vendor	Product	Versions
Linux	Linux Kernel	< 4.4.274
Linux	Linux Kernel	>= 4.5.0, < 4.9.274
Linux	Linux Kernel	>= 4.10.0, < 4.14.238
Linux	Linux Kernel	>= 4.15.0, < 4.19.196
Linux	Linux Kernel	>= 4.20.0, < 5.4.127
Linux	Linux Kernel	>= 5.5.0, < 5.10.45
Linux	Linux Kernel	>= 5.11.0, < 5.12.12

References

Timeline

Published: Feb 26, 2024
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-46906?

In the Linux kernel, the following vulnerability has been resolved: HID: usbhid: fix info leak in hid_submit_ctrl In hid_submit_ctrl(), the way of calculating the report length doesn't take into account that report->size can be zero. When running the syzkaller reproducer, a report of size 0 causes hid_submit_ctrl) to calculate transfer_buffer_length as 16384. When this urb is passed to the usb core layer, KMSAN reports an info leak of 16384 bytes. To fix this, first modify hid_report_len() to account for the zero report size case by using DIV_ROUND_UP for the division. Then, call it from hid_submit_ctrl().

How severe is CVE-2021-46906?

CVE-2021-46906 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.25% probability of exploitation in the next 30 days.

How do I fix CVE-2021-46906?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.