CVE-2023-53094
📋 TL;DR
This CVE describes a race condition vulnerability in the Linux kernel's Freescale LPUART serial driver during DMA shutdown. It can cause a kernel NULL pointer dereference leading to system crashes or denial of service. Systems using affected Linux kernel versions with Freescale LPUART serial interfaces are vulnerable.
💻 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
Kernel panic leading to system crash and denial of service, potentially requiring physical access to reboot affected systems.
Likely Case
System instability or crashes when serial interfaces are heavily used or during shutdown sequences.
If Mitigated
Minor performance impact during serial operations with proper patching.
🎯 Exploit Status
Exploitation requires triggering the race condition during DMA shutdown, which is timing-dependent and requires access to serial operations.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel trees (commits: 19a98d56dfed, 1be6f2b15f90, 2a36b444cace, 90530e7214c8, 954fc9931f0a)
Vendor Advisory: https://git.kernel.org/stable/c/19a98d56dfedafb25652bdb9cd48a4e73ceba702
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from official kernel.org or distribution vendor. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable LPUART DMA
linuxDisable DMA for LPUART serial interfaces to avoid the race condition
echo 0 > /sys/class/tty/ttyLP*/dma_enable
🧯 If You Can't Patch
- Restrict access to serial console interfaces
- Monitor system logs for kernel panic events and implement automated recovery
🔍 How to Verify
Check if Vulnerable:
Check if system uses Freescale LPUART serial interfaces and review kernel version against patched commitsCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes the fix commits or check that the race condition no longer occurs during serial operations📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- NULL pointer dereference errors in dmesg
- Serial interface error messages
Network Indicators:
- None - this is a local kernel vulnerability
SIEM Query:
source="kernel" AND ("NULL pointer dereference" OR "lpuart_copy_rx_to_tty" OR "kernel panic")🔗 References
- https://git.kernel.org/stable/c/19a98d56dfedafb25652bdb9cd48a4e73ceba702
- https://git.kernel.org/stable/c/1be6f2b15f902c02e055ae0b419ca789200473c9
- https://git.kernel.org/stable/c/2a36b444cace9580380467fd1183bb5e85bcc80a
- https://git.kernel.org/stable/c/90530e7214c8a04dcdde57502d93fa96af288c38
- https://git.kernel.org/stable/c/954fc9931f0aabf272b5674cf468affdd88d3a36
