CVE-2025-39714
📋 TL;DR
A race condition vulnerability in the Linux kernel's USBTV driver allows local attackers to cause a kernel crash (denial of service) by changing TV standards while video streaming is active. This affects systems using USBTV devices with the vulnerable driver. The vulnerability requires local access to the system.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Local privilege escalation leading to kernel panic and system crash, potentially causing data loss or service disruption.
Likely Case
Local denial of service through kernel crash when malicious user changes TV standards during active streaming.
If Mitigated
Minimal impact with proper access controls limiting local user privileges and no USBTV devices attached.
🎯 Exploit Status
Exploitation requires local access, USBTV device, and timing to change TV standards during active streaming.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions with commits 3d83d0b5ae5045a7a246ed116b5f6c688a12f9e9, 5427dda195d6baf23028196fd55a0c90f66ffa61, 7e40e0bb778907b2441bff68d73c3eb6b6cd319f, 9f886d21e235c4bd038cb20f6696084304197ab3, c35e7c7a004ef379a1ae7c7486d4829419acad1d
Vendor Advisory: https://git.kernel.org/stable/c/3d83d0b5ae5045a7a246ed116b5f6c688a12f9e9
Restart Required: No
Instructions:
1. Update Linux kernel to patched version from distribution vendor. 2. Rebuild kernel if using custom kernel with patches applied. 3. No reboot required for driver module; unload and reload usbtv module if already loaded.
🔧 Temporary Workarounds
Disable USBTV driver
allPrevent loading of vulnerable usbtv kernel module
echo 'blacklist usbtv' >> /etc/modprobe.d/blacklist.conf
rmmod usbtv
Restrict access to video devices
allLimit which users can access USBTV video devices
chmod 600 /dev/video*
setfacl -m u:trusteduser:rw /dev/video0
🧯 If You Can't Patch
- Remove USBTV hardware devices from vulnerable systems
- Implement strict access controls to prevent unauthorized users from accessing video streaming applications
🔍 How to Verify
Check if Vulnerable:
Check if usbtv module is loaded: lsmod | grep usbtv. Check kernel version against patched commits.Check Version:
uname -rVerify Fix Applied:
Verify kernel includes fix commits: git log --oneline | grep -E '3d83d0b5|5427dda1|7e40e0bb|9f886d21|c35e7c7a'📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/kern.log or dmesg
- USBTV driver error messages
- System crash/reboot events
Network Indicators:
- None - local exploitation only
SIEM Query:
source="kernel" AND ("panic" OR "Oops" OR "usbtv")🔗 References
- https://git.kernel.org/stable/c/3d83d0b5ae5045a7a246ed116b5f6c688a12f9e9
- https://git.kernel.org/stable/c/5427dda195d6baf23028196fd55a0c90f66ffa61
- https://git.kernel.org/stable/c/7e40e0bb778907b2441bff68d73c3eb6b6cd319f
- https://git.kernel.org/stable/c/9f886d21e235c4bd038cb20f6696084304197ab3
- https://git.kernel.org/stable/c/c35e7c7a004ef379a1ae7c7486d4829419acad1d
- https://git.kernel.org/stable/c/c3d75524e10021aa5c223d94da4996640aed46c0
- https://git.kernel.org/stable/c/ee7bade8b9244834229b12b6e1e724939bedd484
- https://git.kernel.org/stable/c/ef9b3c22405192afaa279077ddd45a51db90b83d
- https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
