CVE-2022-48771
📋 TL;DR
This Linux kernel vulnerability in the vmwgfx driver allows use-after-free exploitation when a usercopy operation fails, leaving a stale file descriptor that references freed memory. Attackers with local access can potentially escalate privileges or crash the system. Systems running affected Linux kernel versions with VMware graphics support are vulnerable.
💻 Affected Systems
- Linux kernel with vmwgfx 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 →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 privilege escalation to root, kernel memory corruption leading to system compromise or denial of service.
Likely Case
Local privilege escalation allowing attackers to gain elevated permissions on the affected system.
If Mitigated
Limited impact if proper access controls restrict local user accounts and SELinux/AppArmor are properly configured.
🎯 Exploit Status
Requires local access and knowledge of kernel exploitation techniques. No public exploits known at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel commits: 0008a0c78fc33a84e2212a7c04e6b21a36ca6f4d, 1d833b27fb708d6fdf5de9f6b3a8be4bd4321565, 6066977961fc6f437bc064f628cf9b0e4571c56c, 84b1259fe36ae0915f3d6ddcea6377779de48b82, a0f90c8815706981c483a652a6aefca51a5e191c
Vendor Advisory: https://git.kernel.org/stable/c/0008a0c78fc33a84e2212a7c04e6b21a36ca6f4d
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Check your distribution's security advisories for specific patched versions. 3. Reboot the system after kernel update.
🔧 Temporary Workarounds
Disable vmwgfx driver
linuxPrevent loading of the vulnerable vmwgfx driver module
echo 'blacklist vmwgfx' >> /etc/modprobe.d/blacklist-vmwgfx.conf
rmmod vmwgfx
🧯 If You Can't Patch
- Restrict local user access to minimize attack surface
- Implement strict SELinux/AppArmor policies to limit kernel access
🔍 How to Verify
Check if Vulnerable:
Check if vmwgfx module is loaded: lsmod | grep vmwgfx. Check kernel version against patched versions for your distribution.Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated to patched version and vmwgfx module version matches fixed commits.📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages related to vmwgfx or use-after-free
- Failed usercopy operations in kernel logs
Network Indicators:
- No network indicators - local exploitation only
SIEM Query:
Search for kernel panic logs or vmwgfx-related error messages in system logs🔗 References
- https://git.kernel.org/stable/c/0008a0c78fc33a84e2212a7c04e6b21a36ca6f4d
- https://git.kernel.org/stable/c/1d833b27fb708d6fdf5de9f6b3a8be4bd4321565
- https://git.kernel.org/stable/c/6066977961fc6f437bc064f628cf9b0e4571c56c
- https://git.kernel.org/stable/c/84b1259fe36ae0915f3d6ddcea6377779de48b82
- https://git.kernel.org/stable/c/a0f90c8815706981c483a652a6aefca51a5e191c
- https://git.kernel.org/stable/c/ae2b20f27732fe92055d9e7b350abc5cdf3e2414
- https://git.kernel.org/stable/c/e8d092a62449dcfc73517ca43963d2b8f44d0516
- https://git.kernel.org/stable/c/0008a0c78fc33a84e2212a7c04e6b21a36ca6f4d
- https://git.kernel.org/stable/c/1d833b27fb708d6fdf5de9f6b3a8be4bd4321565
- https://git.kernel.org/stable/c/6066977961fc6f437bc064f628cf9b0e4571c56c
- https://git.kernel.org/stable/c/84b1259fe36ae0915f3d6ddcea6377779de48b82
- https://git.kernel.org/stable/c/a0f90c8815706981c483a652a6aefca51a5e191c
- https://git.kernel.org/stable/c/ae2b20f27732fe92055d9e7b350abc5cdf3e2414
- https://git.kernel.org/stable/c/e8d092a62449dcfc73517ca43963d2b8f44d0516
