high CVSS 7.1 EPSS <0.1%

CVE-2025-21794·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: HID: hid-thrustmaster: fix stack-out-of-bounds read in usb_check_int_endpoints() Syzbot[1] has detected a stack-out-of-bounds read of the ep_addr array from hid-thrustmaster driver. This array is passed to usb_check_int_endpoints function from usb.c core driver, which executes a for loop that iterates over the elements of the passed array. Not finding a null element at the end of the array, it tries to read the next, non-existent element, crashing the kernel. To fix this, a 0 element was added at the end of the array to break the for loop. [1] https://syzkaller.appspot.com/bug?extid=9c9179ac46169c56c1ad

Severity
high
Software
Kernel
Fixed in
6.13.4
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at <0.1% — higher than 11% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Read the two together. CVE-2025-21794 scores 7.1 on CVSS, so a successful attack would be serious — but at <0.1%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.

Affected versions

From: 6.13.2

Until: 6.13.4

Fixed in: 6.13.4

How to fix this CVE

Update your Linux kernel to version 6.13.4 or later to resolve a stack buffer overflow vulnerability in the Thrustmaster HID driver. The vulnerability occurs when the usb_check_int_endpoints function attempts to read beyond an improperly terminated array, potentially causing a kernel crash. Patch your system immediately if you are running kernel versions 6.13.2 through 6.13.3 and use Thrustmaster gaming devices.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Check your current kernel version: uname -r
  2. Verify if the Thrustmaster driver is loaded: lsmod | grep hid_thrustmaster
  3. Search kernel logs for stack-out-of-bounds errors: sudo journalctl -b | grep -i 'stack-out-of-bounds\|kasan\|thrustmaster'
  4. After patching, confirm the new kernel version: uname -r (should be 6.13.4 or later)

FAQ

What is CVE-2025-21794?

This vulnerability is a stack buffer over-read in the Thrustmaster HID driver's endpoint validation routine. An improperly terminated array causes the kernel to attempt reading memory beyond allocated bounds, triggering a kernel panic on systems with this driver active.

Is CVE-2025-21794 being actively exploited?

No, according to CISA KEV data, this vulnerability is not currently being actively exploited in the wild, and no public exploits are available.

What versions of Kernel are affected by CVE-2025-21794?

Kernel versions 6.13.2, 6.13.3, and 6.13.4 (before the fix) are affected. Versions prior to 6.13.2 and 6.13.4 with the patch applied are not vulnerable.

How do I check if my server is vulnerable to CVE-2025-21794?

Run 'uname -r' to check your kernel version. If it shows 6.13.2 or 6.13.3, and you have Thrustmaster gaming hardware, you are vulnerable. Cross-reference with 'lsmod | grep hid_thrustmaster' to confirm the driver is present.

Does Defensia detect CVE-2025-21794?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If the Linux kernel is installed on a monitored server, CVE-2025-21794 will appear in your dashboard with remediation steps.

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References

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