CVE-2025-39679
📋 TL;DR
This CVE describes a memory leak vulnerability in the Linux kernel's Nouveau graphics driver. When an invalid nvif_vmm_type is provided to the nvif_vmm_ctor() function, the system fails to properly free allocated memory before returning an error. This affects systems using the Nouveau open-source NVIDIA graphics driver.
💻 Affected Systems
- Linux kernel with Nouveau 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 →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 kernel memory exhaustion, causing system instability, denial of service, or potential privilege escalation if combined with other vulnerabilities.
Likely Case
Local attackers could trigger the memory leak repeatedly to degrade system performance or cause kernel panics, resulting in denial of service.
If Mitigated
With proper access controls and monitoring, impact is limited to local denial of service affecting only systems using the vulnerable Nouveau driver.
🎯 Exploit Status
Exploitation requires local access and knowledge of how to trigger the invalid nvif_vmm_type condition. No public exploits are known at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing the fix commits: 72553fe19317fe93cb8591c83095c446bc7fe292, 7d9110e3b35d08832661da1a1fc2d24455981a04, bb8aeaa3191b617c6faf8ae937252e059673b7ea, cabcb52d76d3d42f16c344a96e098dd9d18602f8
Vendor Advisory: https://git.kernel.org/stable/c/72553fe19317fe93cb8591c83095c446bc7fe292
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Reboot system to load new kernel. 3. Verify Nouveau driver is using patched kernel code.
🔧 Temporary Workarounds
Disable Nouveau driver
LinuxTemporarily disable the vulnerable Nouveau graphics driver
echo 'blacklist nouveau' >> /etc/modprobe.d/blacklist-nouveau.conf
update-initramfs -u
reboot
🧯 If You Can't Patch
- Restrict local user access to systems using Nouveau driver
- Monitor kernel memory usage for abnormal patterns indicating potential exploitation
🔍 How to Verify
Check if Vulnerable:
Check if system uses Nouveau driver: lsmod | grep nouveau. Check kernel version against affected ranges.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits: uname -r and check git commit history. Confirm Nouveau driver loads without issues.📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages
- Out of memory errors in kernel logs
- System instability reports
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
Search for: 'kernel: Out of memory' OR 'kernel: BUG' OR 'kernel: oops' on systems using Nouveau driver