CVE-2025-37996
📋 TL;DR
A memory management vulnerability in the Linux kernel's KVM (Kernel-based Virtual Machine) for ARM64 systems allows uninitialized memory pointer usage in the user_mem_abort() function. This can cause kernel crashes or instability when handling virtual machine memory operations. The vulnerability affects systems running Linux with KVM virtualization on ARM64 hardware.
💻 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 →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
Kernel panic leading to system crash and denial of service, potentially affecting all virtual machines on the host
Likely Case
System instability or crashes when specific KVM memory operations are performed, particularly during stage-2 page table allocations
If Mitigated
No impact if KVM is not used or if the vulnerable code path is not triggered
🎯 Exploit Status
Exploitation requires local access and ability to trigger specific KVM memory operations. The vulnerability is in error handling code paths.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing fixes from commits 157dbc4a321f5bb6f8b6c724d12ba720a90f1a7c and a26d50f8a4a5049e956984797b5d0dedea4bbb18
Vendor Advisory: https://git.kernel.org/stable/c/157dbc4a321f5bb6f8b6c724d12ba720a90f1a7c
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Check with your distribution for backported patches. 3. Reboot the system to load the new kernel.
🔧 Temporary Workarounds
Disable KVM on ARM64
linuxPrevent the vulnerable code from being executed by disabling KVM virtualization
echo 'blacklist kvm' >> /etc/modprobe.d/blacklist.conf
rmmod kvm
🧯 If You Can't Patch
- Restrict KVM access to trusted users only
- Monitor system logs for kernel panics or instability related to KVM operations
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if KVM modules are loaded: uname -r && lsmod | grep kvmCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits or check with distribution-specific security updates📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- KVM-related error messages in dmesg
- System instability during VM operations
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND ("panic" OR "KVM" OR "user_mem_abort")