CVE-2023-52938
📋 TL;DR
A null pointer dereference vulnerability in the Linux kernel's USB Type-C UCSI driver allows local attackers to cause a kernel panic or system crash by triggering port resume operations before ports are properly registered. This affects Linux systems with USB Type-C hardware and the UCSI driver enabled.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to system crash and denial of service, potentially causing data loss or service disruption.
Likely Case
System crash requiring reboot, resulting in temporary denial of service.
If Mitigated
Minimal impact with proper kernel hardening and privilege separation limiting local access.
🎯 Exploit Status
Requires local access and ability to trigger USB Type-C port operations; race condition exploitation needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits f82060da749c611ed427523b6d1605d87338aac1 or fdd11d7136fd070b3a74d6d8799d9eac28a57fc5
Vendor Advisory: https://git.kernel.org/stable/c/f82060da749c611ed427523b6d1605d87338aac1
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version. 2. Reboot system to load new kernel. 3. Verify kernel version matches patched release.
🔧 Temporary Workarounds
Disable UCSI driver
linuxPrevent loading of vulnerable USB Type-C UCSI driver module
echo 'blacklist ucsi' >> /etc/modprobe.d/blacklist.conf
rmmod ucsi
Restrict local access
allLimit user access to system to reduce attack surface
🧯 If You Can't Patch
- Implement strict access controls to prevent local users from executing privileged operations
- Monitor system logs for kernel panic events and implement crash recovery automation
🔍 How to Verify
Check if Vulnerable:
Check if UCSI module is loaded: lsmod | grep ucsi AND check kernel version against patched releasesCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits and test USB Type-C functionality📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- Null pointer dereference errors in dmesg
- System crash/reboot events
Network Indicators:
- None - local vulnerability
SIEM Query:
source="kernel" AND ("panic" OR "NULL pointer dereference" OR "UCSI")