CVE-2025-38719
📋 TL;DR
A division by zero vulnerability in the Linux kernel's hibmcge network driver allows local attackers to cause a kernel panic when accessing debugfs while the network port is down. This affects Linux systems using the hibmcge driver, primarily those with HiSilicon network hardware. The vulnerability requires local access to trigger.
💻 Affected Systems
- Linux kernel with hibmcge driver
📦 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
Local denial of service causing kernel panic and system crash, requiring physical or remote console access to reboot.
Likely Case
Local denial of service causing system instability or crash when debugfs is accessed with network port down.
If Mitigated
No impact if debugfs is disabled or network port remains up, or if patched kernel is used.
🎯 Exploit Status
Requires local access and ability to trigger debugfs operations while network port is down. Not trivial but straightforward for knowledgeable attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patched in Linux kernel stable branches (commits 475e06113c615dafd44262d6d6bd37786f7f4206, 7004b26f0b64331143eb0b312e77a357a11427ce, c945e1ad4f3b77166a3215dabc0c6c980d4a9c73)
Vendor Advisory: https://git.kernel.org/stable/c/475e06113c615dafd44262d6d6bd37786f7f4206
Restart Required: No
Instructions:
1. Update Linux kernel to patched version from distribution vendor. 2. Apply kernel patch if compiling from source. 3. Reboot to load new kernel.
🔧 Temporary Workarounds
Disable debugfs access
LinuxPrevent non-root users from accessing debugfs to block trigger condition.
mount -o remount,nodev,noexec,nosuid /sys/kernel/debug
Unload hibmcge driver
LinuxRemove vulnerable driver if not needed for system functionality.
rmmod hibmcge
🧯 If You Can't Patch
- Restrict debugfs access to root only using mount options.
- Ensure network ports using hibmcge driver remain up and monitored.
🔍 How to Verify
Check if Vulnerable:
Check if hibmcge module is loaded: lsmod | grep hibmcge. Check kernel version against patched releases.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes patch commit or is from distribution with fix applied.📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- Division by zero errors in kernel logs
- System crash/reboot events
Network Indicators:
- None - local exploit only
SIEM Query:
Search for kernel panic events or division by zero errors in system logs.