CVE-2023-53636
📋 TL;DR
This CVE describes a use-after-free vulnerability in the Linux kernel's Microchip clock driver. When auxiliary device registration fails, the release callback can be called twice, potentially allowing local attackers to execute arbitrary code or crash the system. This affects Linux systems using the affected Microchip clock driver.
💻 Affected Systems
- Linux kernel with Microchip clock driver
📦 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 →⚠️ Risk & Real-World Impact
Worst Case
Local privilege escalation to kernel mode, allowing complete system compromise including data theft, persistence installation, or denial of service.
Likely Case
Kernel panic leading to system crash and denial of service, requiring physical or remote console access to reboot.
If Mitigated
No impact if the vulnerable driver is not loaded or the system has been patched.
🎯 Exploit Status
Requires local access and knowledge of kernel exploitation techniques. No public exploits have been disclosed as of the CVE publication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel stable releases containing commits 5b4052aa956e11bcd19e50ca559eb38dcb46201b, 7455b7007b9e93bcc2bc9c1c6c73a228e3152069, 934406b2d42eaf3fc57f5546cc68ff7ab9680bb3, or d7d6dacf39ed102d7667721ca1700022c9c8b11a
Vendor Advisory: https://git.kernel.org/stable/c/5b4052aa956e11bcd19e50ca559eb38dcb46201b
Restart Required: Yes
Instructions:
1. Update Linux kernel to a patched version from your distribution's repositories. 2. Reboot the system to load the new kernel. 3. Verify the kernel version after reboot.
🔧 Temporary Workarounds
Disable Microchip clock driver
linuxPrevent loading of the vulnerable driver module
echo 'blacklist clk-microchip' >> /etc/modprobe.d/blacklist.conf
rmmod clk_microchip
🧯 If You Can't Patch
- Restrict local user access to systems with the vulnerable driver loaded
- Implement strict privilege separation and limit shell access to trusted users only
🔍 How to Verify
Check if Vulnerable:
Check if the Microchip clock driver is loaded: lsmod | grep clk_microchip. If loaded, check kernel version against patched releases.Check Version:
uname -rVerify Fix Applied:
Verify kernel version after update and ensure the driver still functions correctly for required hardware.📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages
- System crashes/panics related to clk_microchip
- Failed auxiliary device registration in kernel logs
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="kernel" AND ("clk_microchip" OR "auxiliary_device" OR "use-after-free")