CVE-2025-38376 usb: chipidea: udc: disconnect/reconnect from host when do suspend/resume
A race condition in the Linux kernel USB chipidea driver causes a system hang during suspend/resume if data transfer is active, requiring a kernel patch.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-38376?
CVE-2025-38376 is a medium-severity denial of service vulnerability in Linux kernel, published on 25 Jul 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
usb: chipidea: udc: disconnect/reconnect from host when do suspend/resume
Shawn and John reported a hang issue during system suspend as below:
- USB gadget is enabled as Ethernet - There is data transfer over USB Ethernet (scp a big file between host and device) - Device is going in/out suspend (echo mem > /sys/power/state)
The root cause is the USB device controller is suspended but the USB bus is still active which caused the USB host continues to transfer data with device and the device continues to queue USB requests (in this case, a delayed TCP ACK packet trigger the issue) after controller is suspended, however the USB controller clock is already gated off. Then if udc driver access registers after that point, the system will hang.
The correct way to avoid such issue is to disconnect device from host when the USB bus is not at suspend state. Then the host will receive disconnect event and stop data transfer in time. To continue make USB gadget device work after system resume, this will reconnect device automatically.
To make usb wakeup work if USB bus is already at suspend state, this will keep connection for it only when USB device controller has enabled wakeup capability.
Which versions are affected by CVE-2025-38376?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-38376?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-38376 being exploited?
There is no known exploitation of CVE-2025-38376 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-65696, BELL-CVE-2025-38376, DEBIAN-CVE-2025-38376, GHSA-q9hc-qj7m-hpc9, ROOT-OS-UBUNTU-2404-CVE-2025-38376, UBUNTU-CVE-2025-38376.