CVE-2022-50394 – This CVE describes an out-of-bounds memory acce... (How to Fix)

Q: What is the severity of CVE-2022-50394?

CVE-2022-50394 has a CVSS score of 7.1 (HIGH). This CVE describes an out-of-bounds memory access vulnerability in the Linux kernel's i2c subsystem, specifically in the ismt_access() function. Attackers with local access can trigger this vulnerability by providing specially crafted input to cause kernel memory corruption, potentially leading to system crashes or privilege escalation. This affects Linux systems using the Intel SMBus Message Transfer (iSMT) controller driver.

📋 TL;DR

This CVE describes an out-of-bounds memory access vulnerability in the Linux kernel's i2c subsystem, specifically in the ismt_access() function. Attackers with local access can trigger this vulnerability by providing specially crafted input to cause kernel memory corruption, potentially leading to system crashes or privilege escalation. This affects Linux systems using the Intel SMBus Message Transfer (iSMT) controller driver.

💻 Affected Systems

Products:

Linux kernel

Versions: Kernel versions before the fix commits (specific versions vary by distribution)

Operating Systems: Linux distributions using affected kernel versions

Default Config Vulnerable: ⚠️ Yes

Notes: Requires the i2c-ismt driver to be loaded and accessible. Systems with Intel SMBus Message Transfer controllers are affected.

📦 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 →

⚠️ Risk & Real-World Impact

🔴

Worst Case

Kernel panic leading to denial of service, or potential privilege escalation to root if attackers can control memory corruption to execute arbitrary code.

🟠

Likely Case

System crash or kernel panic causing denial of service, requiring system reboot.

🟢

If Mitigated

Minimal impact if proper input validation is implemented to prevent out-of-bounds access.

🌐 Internet-Facing: LOW - This is a local kernel vulnerability requiring access to the i2c device interface.

🏢 Internal Only: MEDIUM - Local attackers with access to i2c device nodes could exploit this to crash systems or potentially escalate privileges.

🎯 Exploit Status

Public PoC: ⚠️ Yes

Weaponized: LIKELY

Unauthenticated Exploit: ✅ No

Complexity: MEDIUM

The vulnerability requires local access to the i2c device interface. The log output shows 'ismt_poc' indicating proof-of-concept code exists.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Kernel versions containing the fix commits: 03b7ef7a6c5ca1ff553470166b4919db88b810f6 and related commits

Vendor Advisory: https://git.kernel.org/stable/c/03b7ef7a6c5ca1ff553470166b4919db88b810f6

Restart Required: Yes

Instructions:

1. Update Linux kernel to patched version from your distribution vendor. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.

🔧 Temporary Workarounds

Disable i2c-ismt module

linux

Prevent loading of the vulnerable i2c-ismt driver module

echo 'blacklist i2c-ismt' >> /etc/modprobe.d/blacklist-ismt.conf
rmmod i2c_ismt

Restrict i2c device access

linux

Change permissions on i2c device nodes to restrict access

chmod 600 /dev/i2c-*
chown root:root /dev/i2c-*

🧯 If You Can't Patch

Implement strict access controls on i2c device nodes (/dev/i2c-*)
Monitor system logs for i2c access attempts and kernel panic events

🔍 How to Verify

Check if Vulnerable:

Check if i2c-ismt module is loaded: lsmod | grep ismt. Check kernel version against patched versions from your distribution.

Check Version:

uname -r

Verify Fix Applied:

Verify kernel version is updated to patched version and i2c-ismt module functions normally without crashes.

📡 Detection & Monitoring

Log Indicators:

Kernel logs showing 'BUG: KASAN: out-of-bounds in ismt_access'
i2c device access logs with large block sizes
System crashes or kernel panics related to i2c

Network Indicators:

None - this is a local vulnerability

SIEM Query:

source="kernel" AND ("ismt_access" OR "out-of-bounds" OR "KASAN")

📊 Metadata

CVE ID: CVE-2022-50394

CVSS v3 Score: 7.1 (HIGH)

CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

CWE: CWE-125

EPSS Score: 0.01% exploit probability (1.2th percentile)

Published: September 18, 2025

Last Updated: January 14, 2026

🔗 References

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