CVE-2022-49058
📋 TL;DR
This CVE describes a buffer overflow vulnerability in the Linux kernel's CIFS filesystem driver when handling symbolic links. An attacker could exploit this to execute arbitrary code or cause a denial of service on affected systems. The vulnerability affects Linux systems with CIFS/SMB support enabled.
💻 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 →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
Remote code execution with kernel privileges leading to complete system compromise
Likely Case
Kernel panic or system crash causing denial of service
If Mitigated
No impact if patched or CIFS not in use
🎯 Exploit Status
Requires ability to create or manipulate symbolic links on CIFS shares
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions with commit 1316c28569a80ab3596eeab05bf5e01991e7e739 or later
Vendor Advisory: https://git.kernel.org/stable/c/1316c28569a80ab3596eeab05bf5e01991e7e739
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution vendor. 2. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable CIFS filesystem
LinuxPrevent loading of CIFS kernel module to eliminate attack surface
echo 'install cifs /bin/false' >> /etc/modprobe.d/disable-cifs.conf
rmmod cifs
🧯 If You Can't Patch
- Restrict CIFS/SMB access to trusted networks only
- Implement strict access controls on CIFS shares to prevent unauthorized symlink creation
🔍 How to Verify
Check if Vulnerable:
Check kernel version and verify if CIFS module is loaded: lsmod | grep cifsCheck Version:
uname -rVerify Fix Applied:
Check kernel version is patched and verify CIFS module version📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- CIFS error messages related to symlink handling
- System crash dumps
Network Indicators:
- Unusual CIFS/SMB traffic patterns
- Multiple failed symlink operations
SIEM Query:
source="kernel" AND ("panic" OR "oops") AND "cifs"🔗 References
- https://git.kernel.org/stable/c/1316c28569a80ab3596eeab05bf5e01991e7e739
- https://git.kernel.org/stable/c/22d658c6c5affed10c8907e67160cef0b6c92186
- https://git.kernel.org/stable/c/3e582749e742e662a8e9bb37cffac62dccaaa1e2
- https://git.kernel.org/stable/c/4e166a41180be2f1e66bbb6d46448e80a9a5ec05
- https://git.kernel.org/stable/c/515e7ba11ef043d6febe69389949c8ef5f25e9d0
- https://git.kernel.org/stable/c/64c4a37ac04eeb43c42d272f6e6c8c12bfcf4304
- https://git.kernel.org/stable/c/9901b07ba42b39266b34a888e48d7306fd707bee
- https://git.kernel.org/stable/c/eb5f51756944735ac70cd8bb38637cc202e29c91
