CVE-2022-49509
📋 TL;DR
A use-after-free vulnerability in the Linux kernel's MAX9286 I2C camera bridge driver causes a kernel oops (crash) when removing the module. This affects systems using the MAX9286 hardware with the vulnerable driver, potentially leading to denial of service. The issue occurs due to incorrect pointer handling between I2C client data and V4L2 subdevice structures.
💻 Affected Systems
- Linux kernel with MAX9286 I2C camera bridge 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
Kernel panic leading to system crash and denial of service, requiring physical or remote reboot.
Likely Case
System instability or crash when removing the MAX9286 module, causing temporary service disruption.
If Mitigated
No impact if patched or module removal is avoided.
🎯 Exploit Status
Requires local access and CAP_SYS_MODULE capability to load/unload modules. Triggered by removing the max9286 module.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel stable releases containing fixes from commits: 365ab7ebc24e, 579c77595dbb, 9dd783274c89, a4ec75df7057
Vendor Advisory: https://git.kernel.org/stable/c/365ab7ebc24eebb42b9e020aeb440d51af8960cd
Restart Required: No
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. For custom kernels, apply patches from kernel.org. 3. Rebuild and install kernel if compiling from source. 4. No reboot required for module updates, but kernel update requires reboot.
🔧 Temporary Workarounds
Prevent module removal
LinuxRestrict module unloading capabilities to prevent triggering the vulnerability
echo 1 > /sys/module/max9286/parameters/refcnt
chmod 400 /sys/module/max9286/initstate
🧯 If You Can't Patch
- Restrict module loading/unloading capabilities using kernel.modules_disabled=1 or capabilities
- Monitor for module removal attempts and alert on rmmod max9286 commands
🔍 How to Verify
Check if Vulnerable:
Check if max9286 module is loaded: lsmod | grep max9286. Check kernel version: uname -r and compare with patched versions.Check Version:
uname -rVerify Fix Applied:
After update, attempt safe module removal test in controlled environment or verify kernel contains fix commits.📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages mentioning max9286_remove or i2c_mux_del_adapters
- System crash/panic logs during module removal
Network Indicators:
- None - local vulnerability only
SIEM Query:
process.name="rmmod" AND process.args="max9286" OR kernel.message="*max9286*" OR kernel.message="*i2c_mux_del_adapters*"