CVE-2025-39700
📋 TL;DR
A vulnerability in the Linux kernel's DAMON (Data Access MONitor) subsystem allows kernel panic when invalid memory migration requests are made. This affects systems using DAMOS (DAMON Operation Schemes) with MIGRATE actions on Linux kernels with the vulnerable code. Attackers with local access can trigger denial of service by exploiting this flaw.
💻 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
Kernel panic leading to system crash and denial of service, potentially causing data loss or service disruption.
Likely Case
Local denial of service through kernel panic when malicious or malformed DAMOS migration requests are made.
If Mitigated
Minimal impact if DAMON/DAMOS features are disabled or proper input validation is implemented.
🎯 Exploit Status
Requires local access and ability to make DAMOS migration requests. Exploitation requires understanding of DAMON subsystem and memory management.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patched in kernel commits 7c303fa1f311, 7e6c3130690a, 9d0c2d15aff9
Vendor Advisory: https://git.kernel.org/stable/c/7c303fa1f311aadc17fa82b7bbf776412adf45de
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Reboot system to load new kernel. 3. Verify DAMON/DAMOS functionality if needed.
🔧 Temporary Workarounds
Disable DAMON/DAMOS features
LinuxDisable the DAMON memory management subsystem if not required
echo 'blacklist damon' >> /etc/modprobe.d/blacklist.conf
reboot
🧯 If You Can't Patch
- Restrict access to DAMON interfaces to trusted users only
- Monitor system logs for kernel panic events related to DAMON migration
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if DAMON is enabled: 'uname -r' and check /proc/modules for damon modulesCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits: 'uname -r' and check git log for commit hashes📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages mentioning DAMON, damon_migrate_pages, or migration faults
- BUG: unable to handle page fault in damon_migrate_pages
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND ("damon_migrate" OR "DAMON" OR "migration fault")