CVE-2022-49186
📋 TL;DR
A Linux kernel vulnerability in the clk: visconti driver allows local attackers to cause an array overflow by exploiting improper type casting. This affects systems using Toshiba Visconti ARM SoCs with vulnerable kernel versions, potentially leading to kernel crashes or privilege escalation.
💻 Affected Systems
- Linux kernel with clk: visconti 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 →⚠️ Risk & Real-World Impact
Worst Case
Local privilege escalation to root, kernel panic causing system crash, or arbitrary code execution in kernel context.
Likely Case
Kernel panic leading to denial of service (system crash) when malicious user triggers the overflow.
If Mitigated
No impact if patched or if system doesn't use Visconti clock controller hardware.
🎯 Exploit Status
Requires local access and knowledge of driver internals. No public exploits known as of analysis.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits 2723543c1d60278d5aef1c4ad732dbad24b84a81 and c5601e0720ce1a3ad895f94a5838530edde01ed3
Vendor Advisory: https://git.kernel.org/stable/c/2723543c1d60278d5aef1c4ad732dbad24b84a81
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution. 2. Reboot system to load new kernel. 3. Verify driver is no longer vulnerable.
🔧 Temporary Workarounds
Disable visconti clock controller
linuxRemove or disable the vulnerable driver if not needed
modprobe -r clk_visconti
echo 'blacklist clk_visconti' >> /etc/modprobe.d/blacklist.conf
🧯 If You Can't Patch
- Restrict local user access to systems with vulnerable kernels
- Implement strict privilege separation and limit user capabilities
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if visconti driver is loaded: 'uname -r' and 'lsmod | grep visconti'Check Version:
uname -rVerify Fix Applied:
Verify kernel version is after fix commits and driver functions correctly📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages
- System crash/reboot logs
- Driver initialization failures
Network Indicators:
- None - local exploit only
SIEM Query:
kernel: "Oops" OR "general protection fault" AND process:"clk_visconti"