CVE-2025-37985
📋 TL;DR
A race condition vulnerability in the Linux kernel's USB WDM driver allows opening a character device while its URBs are still poisoned, potentially leading to use-after-free conditions. This affects Linux systems using USB WWAN devices. Attackers could potentially crash the kernel or execute arbitrary code.
💻 Affected Systems
- Linux kernel
📦 What is this software?
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic, system crash, or potential arbitrary code execution with kernel privileges leading to complete system compromise.
Likely Case
System instability, kernel crashes, or denial of service affecting USB WWAN functionality.
If Mitigated
Minor system instability or USB WWAN device malfunctions if proper isolation and privilege separation are in place.
🎯 Exploit Status
Requires race condition timing and access to USB WWAN device; exploitation may be challenging but possible with local access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits: 217fe1fc7d112595a793e02b306710e702eac492, 52ae15c665b5fe5876655aaccc3ef70560b0e314, 54f7f8978af19f899dec80bcc71c8d4855dfbd72, b02a3fef3e8c8fe5a0a266f7a14f38cc608fb167, c1846ed4eb527bdfe6b3b7dd2c78e2af4bf98f4f
Vendor Advisory: https://git.kernel.org/stable/c/217fe1fc7d112595a793e02b306710e702eac492
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution's repositories. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable USB WWAN support
linuxPrevent loading of vulnerable USB WDM driver by blacklisting or disabling module
echo 'blacklist cdc-wdm' >> /etc/modprobe.d/blacklist.conf
update-initramfs -u
Restrict USB device access
linuxUse udev rules to restrict access to USB WWAN devices
echo 'SUBSYSTEM=="usb", ATTRS{idVendor}=="vendor_id", ATTRS{idProduct}=="product_id", MODE="0660", GROUP="trusted"' >> /etc/udev/rules.d/99-usb-restrict.rules
🧯 If You Can't Patch
- Restrict physical access to USB ports and USB devices
- Implement strict user privilege separation and limit access to USB devices
🔍 How to Verify
Check if Vulnerable:
Check if USB WDM driver is loaded: lsmod | grep cdc_wdmCheck Version:
uname -rVerify Fix Applied:
Check kernel version includes fix commits or is newer than patched version📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages in /var/log/kern.log or dmesg
- USB-related crash logs
- System instability reports
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND ("oops" OR "panic" OR "BUG") AND ("usb" OR "wdm" OR "wwan")🔗 References
- https://git.kernel.org/stable/c/217fe1fc7d112595a793e02b306710e702eac492
- https://git.kernel.org/stable/c/52ae15c665b5fe5876655aaccc3ef70560b0e314
- https://git.kernel.org/stable/c/54f7f8978af19f899dec80bcc71c8d4855dfbd72
- https://git.kernel.org/stable/c/b02a3fef3e8c8fe5a0a266f7a14f38cc608fb167
- https://git.kernel.org/stable/c/c1846ed4eb527bdfe6b3b7dd2c78e2af4bf98f4f
- https://git.kernel.org/stable/c/e3c9adc69357fcbe6253a2bc2588ee4bbaaedbe9
- https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html
