CVE-2022-48753
📋 TL;DR
This CVE describes a memory leak vulnerability in the Linux kernel's block subsystem. When disk_register_independent_access_ranges fails during kobject initialization, it doesn't properly release memory, causing gradual memory exhaustion. This affects all Linux systems using the affected kernel versions.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Sustained exploitation could lead to complete system memory exhaustion, causing kernel panics, system crashes, and denial of service across all applications.
Likely Case
Gradual memory depletion over time leading to performance degradation, application failures, and potential system instability requiring reboots.
If Mitigated
With proper monitoring and memory limits, impact is limited to performance issues and occasional service restarts rather than complete system failure.
🎯 Exploit Status
Exploitation requires ability to trigger the specific failure condition in disk registration, typically requiring local system access and specific disk operations.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits 83114df32ae779df57e0af99a8ba6c3968b2ba3d and fe4214a07e0b53d2af711f57519e33739c5df23f
Vendor Advisory: https://git.kernel.org/stable/c/83114df32ae779df57e0af99a8ba6c3968b2ba3d
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Check with your distribution vendor for specific patched kernel packages. 3. Reboot system after kernel update.
🔧 Temporary Workarounds
Memory monitoring and limits
linuxImplement strict memory monitoring and cgroup limits to contain memory leak impact
echo 'memory.max: 4G' > /sys/fs/cgroup/memory/your_service/memory.max
echo 'memory.swap.max: 0' > /sys/fs/cgroup/memory/your_service/memory.swap.max
🧯 If You Can't Patch
- Implement aggressive memory monitoring with automated alerts for unusual memory consumption patterns
- Restrict disk operations and block device access to trusted users only to reduce trigger opportunities
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with distribution's patched versions. Vulnerable if running kernel without the fix commits.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes the fix commits: 'uname -r' and check with distribution vendor for patch status📡 Detection & Monitoring
Log Indicators:
- Kernel oom-killer messages
- Memory allocation failures in kernel logs
- Gradually increasing memory usage without corresponding application growth
Network Indicators:
- None - this is a local memory management issue
SIEM Query:
source="kernel" AND ("out of memory" OR "oom-killer" OR "memory allocation failure")