CVE-2023-53359
📋 TL;DR
This CVE describes a memory leak vulnerability in the Linux kernel's USB subsystem 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 systems running affected Linux kernel versions with USB support are potentially 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 →⚠️ Risk & Real-World Impact
Worst Case
Sustained exploitation could lead to kernel memory exhaustion, causing system crashes, denial of service, or potentially enabling other attacks due to resource exhaustion.
Likely Case
Gradual memory leak leading to system performance degradation over time, potentially requiring system reboots to restore normal operation.
If Mitigated
Minimal impact with proper monitoring and memory management controls in place.
🎯 Exploit Status
Exploitation requires ability to trigger USB debugfs operations, typically requiring local access or compromised process.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions with commits 30374434edab20e25776f8ecb4bc9d1e54309487, 6683327b51a601daba32900072349dfa1d4e8fea, c68ece7baf2aa9783b8244482c03010d477d4a93, or cc00340fb1226a2a3a5cf15473ac417da3c952f1
Vendor Advisory: https://git.kernel.org/stable/c/30374434edab20e25776f8ecb4bc9d1e54309487
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution vendor. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable debugfs for USB
LinuxMount debugfs with noexec option or disable USB debugfs functionality
mount -o remount,noexec /sys/kernel/debug
🧯 If You Can't Patch
- Implement strict access controls to limit who can access debugfs directories
- Monitor system memory usage and kernel logs for signs of memory exhaustion
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with patched versions from distribution vendor. Check if USB debugfs is accessible.Check Version:
uname -rVerify Fix Applied:
Verify kernel version matches patched version from vendor. Check that debugfs_lookup_and_remove() is used instead of debugfs_lookup() in USB code.📡 Detection & Monitoring
Log Indicators:
- Kernel oom-killer messages
- Increasing memory usage in /proc/meminfo
- System performance degradation logs
Network Indicators:
- None - local vulnerability only
SIEM Query:
Search for kernel panic logs, memory exhaustion alerts, or abnormal system reboot patterns