CVE-2025-38623
📋 TL;DR
A vulnerability in the Linux kernel's PowerNV PCI hotplug subsystem could cause system instability when PCI devices are unexpectedly removed. This affects Linux systems running on IBM PowerNV platforms with PCI hotplug capabilities, potentially requiring a reboot to recover from device removal events.
💻 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 →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
System becomes unresponsive to PCI hotplug events, requiring a full reboot to restore functionality and potentially causing service disruption.
Likely Case
After surprise removal of a PCI device, the system fails to detect new devices in affected slots until reboot, disrupting hardware maintenance operations.
If Mitigated
With proper patching, hotplug operations proceed normally without requiring system reboots.
🎯 Exploit Status
Requires physical access or authorized hardware management privileges to trigger via device removal; not a remote code execution vulnerability.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in Linux kernel stable branches (commits referenced in CVE)
Vendor Advisory: https://git.kernel.org/stable/c/1d2f63680c5719a5da92639e981c6c9a87fcee08
Restart Required: No
Instructions:
1. Update Linux kernel to version containing fixes 2. Apply kernel patches from stable branches 3. Rebuild kernel if using custom kernel 4. No system reboot required for patch application
🔧 Temporary Workarounds
Avoid surprise device removal
allEnsure all PCI device removals are performed through proper hotplug procedures rather than surprise removal
Use proper hotplug commands before physically removing devices
Disable PCI hotplug if not needed
linuxDisable PCI hotplug functionality if not required for system operation
echo 0 > /sys/bus/pci/slots/*/power
🧯 If You Can't Patch
- Implement strict change control for physical hardware access to PCI slots
- Schedule system reboots after any PCI device maintenance operations
🔍 How to Verify
Check if Vulnerable:
Check if system is PowerNV architecture and has PCI hotplug slots: 'uname -m' should show ppc64le and check /sys/bus/pci/slots/Check Version:
uname -rVerify Fix Applied:
Check kernel version includes fixes from referenced commits: 'uname -r' and verify with git log📡 Detection & Monitoring
Log Indicators:
- Kernel messages about PCI hotplug failures
- PE freeze messages in kernel logs
- Hotplug event timeouts
Network Indicators:
- None - this is a local hardware management issue
SIEM Query:
source="kernel" AND ("pnv_php" OR "PCI hotplug" OR "PE freeze")🔗 References
- https://git.kernel.org/stable/c/1d2f63680c5719a5da92639e981c6c9a87fcee08
- https://git.kernel.org/stable/c/2ec8ec57bb8ebde3e2a015eff80e5d66e6634fe3
- https://git.kernel.org/stable/c/473999ba937eac9776be791deed7c84a21d7880b
- https://git.kernel.org/stable/c/48c6935a34981bb56f35be0774ec1f30c6e386f8
- https://git.kernel.org/stable/c/6e7b24c71e530a6c1d656e73d8a30ee081656844
- https://git.kernel.org/stable/c/6e7b5f922901585b8f11e0d6cda12bda5c59fc8a
- https://git.kernel.org/stable/c/78d20b8c13075eae3d884c21db7a09a6bbdda5b2
- https://git.kernel.org/stable/c/a2a2a6fc2469524caa713036297c542746d148dc
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
