CVE-2023-53417
📋 TL;DR
This CVE describes a memory leak vulnerability in the Linux kernel's USB sl811 driver when using debugfs_lookup() without proper cleanup. The vulnerability allows attackers to gradually exhaust kernel memory over time, potentially leading to system instability or denial of service. All Linux systems using the affected kernel versions with the sl811 USB driver loaded are affected.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Sustained exploitation could exhaust kernel memory, causing system crashes, denial of service, or enabling other attacks through memory pressure.
Likely Case
Gradual memory consumption leading to system instability, performance degradation, or eventual kernel panic if debugfs operations are frequently performed.
If Mitigated
Minimal impact with proper monitoring and memory limits in place, though still represents a resource exhaustion risk.
🎯 Exploit Status
Exploitation requires ability to trigger debugfs operations on the sl811 driver, typically requiring local access or ability to interact with USB subsystem.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patched in stable kernel commits: 04fdfec7b028, 54166af8941d, bb4d5eefb670, e1523c4dbc54
Vendor Advisory: https://git.kernel.org/stable/c/04fdfec7b0286972cb5457ef958c92585447a39f
Restart Required: Yes
Instructions:
1. Update to a patched kernel version from your distribution. 2. Reboot the system to load the new kernel. 3. Verify the fix by checking kernel version or confirming sl811 driver is not leaking memory.
🔧 Temporary Workarounds
Disable debugfs for sl811
LinuxPrevent debugfs operations on the sl811 driver to avoid triggering the memory leak
echo 0 > /sys/kernel/debug/sl811/enable
umount /sys/kernel/debug/sl811
Blacklist sl811 module
LinuxPrevent loading of the vulnerable sl811 driver
echo 'blacklist sl811-hcd' >> /etc/modprobe.d/blacklist.conf
🧯 If You Can't Patch
- Monitor kernel memory usage for unusual increases
- Restrict access to debugfs and USB operations to trusted users only
🔍 How to Verify
Check if Vulnerable:
Check if sl811 module is loaded: lsmod | grep sl811. Check kernel version against patched versions.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes one of the fix commits. Monitor /proc/meminfo and kernel logs for memory leak indicators after fix.📡 Detection & Monitoring
Log Indicators:
- Kernel oom-killer messages
- Increasing kernel memory usage in /proc/meminfo
- System instability or crashes after USB operations
Network Indicators:
- None - local vulnerability only
SIEM Query:
kernel: "Out of memory: Kill process" OR "sl811" AND ("debugfs" OR "memory leak")