CVE-2022-50283
📋 TL;DR
This CVE-2022-50283 is a use-after-free vulnerability in the Linux kernel's MTD subsystem caused by missing of_node_get() calls in dynamic partition code. It allows potential kernel memory corruption and system crashes, affecting Linux systems using MTD devices with dynamic partitions. The vulnerability occurs during device initialization and can lead to kernel panics.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to system crash, potential denial of service, or in rare cases, local privilege escalation if combined with other vulnerabilities.
Likely Case
System crash during boot or device initialization, causing denial of service on affected systems.
If Mitigated
Minor performance impact or no effect if the vulnerable code path isn't triggered.
🎯 Exploit Status
Exploitation requires local access and ability to trigger the vulnerable code path during MTD device initialization.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel commit 12b58961de0bd88b3c7dfa5d21f6d67f4678b780 and backported to stable branches
Vendor Advisory: https://git.kernel.org/stable/c/12b58961de0bd88b3c7dfa5d21f6d67f4678b780
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix. 2. Check your distribution's security advisories for backported patches. 3. Reboot the system after kernel update.
🔧 Temporary Workarounds
Disable dynamic MTD partitions
linuxAvoid using dynamic MTD partitions if possible, though this may not be feasible for all systems.
Modify kernel command line or device tree to use static partitions instead of dynamic ones
🧯 If You Can't Patch
- Restrict physical and local access to affected systems
- Monitor system logs for kernel panic or refcount warnings related to MTD devices
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if MTD devices with dynamic partitions are present: 'cat /proc/mtd' and check kernel logs for refcount warnings during boot.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes the fix commit: 'uname -r' and check distribution patch notes. Monitor for absence of refcount warnings in dmesg.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- refcount_t: addition on 0; use-after-free warnings in dmesg
- MTD partition creation errors
Network Indicators:
- None - this is a local kernel vulnerability
SIEM Query:
Search for 'refcount_warn_saturate' OR 'use-after-free' AND 'MTD' OR 'gpmi-nand' in kernel logs