CVE-2022-3577: Linux Kernel Privilege Escalation Flaw

CVE-2022-3577 Overview

An out-of-bounds memory write vulnerability has been identified in the Linux kernel's Kid-friendly Wired Controller driver (BigBen). This flaw exists in the bigben_probe function within drivers/hid/hid-bigbenff.c and stems from an incorrect assumption that all BigBen devices have inputs. A local attacker can exploit this vulnerability by connecting a malicious device that breaks this assumption, leading to out-of-bounds memory writes that can crash the system or potentially escalate privileges.

Critical Impact

Local users can crash the system or potentially escalate their privileges by exploiting an out-of-bounds write condition triggered by malicious USB HID devices.

Affected Products

• Linux Kernel (multiple versions affected)
• Linux Kernel 5.19-rc1
• Systems with BigBen HID driver enabled (hid-bigbenff.c)

Discovery Timeline

• 2022-10-20 - CVE CVE-2022-3577 published to NVD
• 2025-05-08 - Last updated in NVD database

Technical Details for CVE-2022-3577

Vulnerability Analysis

This vulnerability is classified as CWE-787 (Out-of-bounds Write) and CWE-401 (Missing Release of Memory after Effective Lifetime). The flaw resides in the BigBen HID driver's probe function, which handles device initialization when a BigBen-compatible game controller is connected to the system.

The root cause is a flawed assumption in the driver code that all BigBen devices will have valid input endpoints. When a malicious or malformed USB HID device is connected that claims to be a BigBen controller but lacks expected input structures, the driver proceeds without proper validation. This leads to memory operations being performed on uninitialized or invalid memory regions.

Since the attack requires local access (physical connection of a malicious USB device or equivalent access), exploitation requires an attacker to either have physical access to the target machine or to trick a user into connecting a malicious device. Once triggered, the out-of-bounds write can corrupt adjacent kernel memory, potentially allowing arbitrary code execution in kernel context.

Root Cause

The vulnerability stems from insufficient input validation in the bigben_probe() function. The driver assumes all devices matching the BigBen HID descriptor will have valid input endpoints configured. When a device violates this assumption by presenting incomplete or malformed descriptors, the driver continues execution with invalid or uninitialized pointers, resulting in out-of-bounds memory writes during the device initialization sequence.

Attack Vector

The attack requires local access to the system. An attacker must connect a specially crafted USB HID device that mimics a BigBen controller but provides malformed or missing input endpoint data. When the kernel's HID subsystem loads the BigBen driver for this malicious device, the bigben_probe() function executes without proper validation, triggering the out-of-bounds write condition.

The vulnerability manifests during device probe initialization in the HID driver subsystem. The specific flaw occurs when the driver attempts to access input device structures that don't exist or are improperly initialized. For technical details on the exact code paths involved, refer to the Linux Kernel Commit Change.

Detection Methods for CVE-2022-3577

Indicators of Compromise

• Unexpected kernel panic or oops messages referencing hid-bigbenff or bigben_probe
• Suspicious USB device connection events for devices identifying as BigBen controllers
• Kernel log entries showing memory corruption or invalid memory access in HID subsystem
• Unusual privilege escalation attempts following USB device connections

Detection Strategies

• Monitor dmesg and kernel logs for error messages related to hid-bigbenff.c or the BigBen driver module
• Implement USB device whitelisting to prevent unauthorized HID devices from being probed
• Use Linux audit subsystem to track USB device connections and HID driver loading events
• Deploy endpoint detection solutions capable of monitoring kernel-level anomalies

Monitoring Recommendations

• Enable kernel auditing for module loading events, specifically for HID-related drivers
• Configure alerts for unexpected USB device enumeration, particularly devices claiming BigBen vendor/product IDs
• Monitor for kernel memory corruption indicators such as SLUB/SLAB debugging warnings
• Implement SentinelOne's kernel-level monitoring to detect privilege escalation attempts following driver exploitation

How to Mitigate CVE-2022-3577

Immediate Actions Required

• Update the Linux kernel to a patched version that includes the security fix
• If unable to update immediately, consider blacklisting the hid-bigbenff module if BigBen controllers are not required
• Restrict physical access to USB ports on critical systems
• Implement USB device authorization policies to prevent untrusted devices from being recognized

Patch Information

The Linux kernel development team has released patches to address this vulnerability. The fix adds proper validation to ensure input endpoints exist before attempting to access them in the bigben_probe() function.

Multiple commits address this issue:

• Linux Kernel Commit Update - char-misc-next branch fix
• Linux Kernel Commit Change - Main kernel fix
• Linux Kernel Commit Modification - Additional fix

Workarounds

• Blacklist the vulnerable driver module by adding blacklist hid-bigbenff to /etc/modprobe.d/blacklist.conf
• Disable USB device auto-probing for untrusted systems using USBGuard or similar tools
• Implement strict physical security controls to prevent unauthorized USB device connections
• Use kernel command line parameters to disable specific HID drivers if not needed

# Blacklist the vulnerable BigBen HID driver module
echo "blacklist hid-bigbenff" | sudo tee /etc/modprobe.d/blacklist-bigben.conf

# Prevent module from loading (requires reboot)
sudo update-initramfs -u

# Alternatively, remove the module if currently loaded
sudo modprobe -r hid-bigbenff