CVE-2023-52781 – A Linux kernel vulnerability in the USB subsyst... (How to Fix)

Q: What is the severity of CVE-2023-52781?

CVE-2023-52781 has a CVSS score of 5.5 (MEDIUM). A Linux kernel vulnerability in the USB subsystem allows an infinite loop condition when processing BOS descriptors. This can lead to denial of service (DoS) by causing kernel hangs or crashes when connecting malicious USB devices. Affects systems running vulnerable Linux kernel versions with USB functionality enabled.

📋 TL;DR

A Linux kernel vulnerability in the USB subsystem allows an infinite loop condition when processing BOS descriptors. This can lead to denial of service (DoS) by causing kernel hangs or crashes when connecting malicious USB devices. Affects systems running vulnerable Linux kernel versions with USB functionality enabled.

💻 Affected Systems

Products:

Linux kernel

Versions: Specific vulnerable versions not explicitly stated in CVE, but patches available for multiple stable branches

Operating Systems: Linux distributions using affected kernel versions

Default Config Vulnerable: ⚠️ Yes

Notes: Requires USB functionality enabled. Systems without USB ports or with USB disabled are not vulnerable.

📦 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 →

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 or system crash requiring physical reboot, potentially causing data loss or service disruption.

🟠

Likely Case

System hang or freeze when connecting a malicious USB device, requiring reboot to restore functionality.

🟢

If Mitigated

No impact if USB functionality is disabled or if proper USB device restrictions are in place.

🌐 Internet-Facing: LOW - Requires physical USB device connection or USB over IP with specific conditions.

🏢 Internal Only: MEDIUM - Malicious USB devices could be connected internally, but requires physical access or USB redirection.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ⚠️ Yes

Complexity: MEDIUM

Exploitation requires ability to connect a specially crafted USB device. No public exploit code known at this time.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Multiple stable kernel versions with fixes: 64c27b7b2357, 7c0244cc311a, 974bba5c118f, 9ef94ec8e52e, f89fef7710b2

Vendor Advisory: https://git.kernel.org/stable/c/64c27b7b2357ddb38b6afebaf46d5bff4d250702

Restart Required: Yes

Instructions:

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

🔧 Temporary Workarounds

Disable USB functionality

linux

Prevent USB device enumeration by disabling USB subsystem

echo 'blacklist usb-storage' > /etc/modprobe.d/disable-usb.conf
update-initramfs -u
reboot

USB device restrictions

linux

Implement USB device authorization policies

Configure udev rules to restrict USB device access
Use USBGuard or similar tools

🧯 If You Can't Patch

Implement strict physical security controls for USB ports
Use USB port blockers or disable USB in BIOS/UEFI where possible

🔍 How to Verify

Check if Vulnerable:

Check kernel version and compare with patched versions from kernel git repository

Check Version:

uname -r

Verify Fix Applied:

Verify kernel version matches or exceeds patched versions listed in fix references

📡 Detection & Monitoring

Log Indicators:

Kernel panic messages
USB subsystem errors in dmesg
System hang/crash events

Network Indicators:

Unusual USB over network traffic if USB/IP is used

SIEM Query:

source="kernel" AND ("panic" OR "BUG" OR "Oops") AND "usb"

📊 Metadata

CVE ID: CVE-2023-52781

CVSS v3 Score: 5.5 (MEDIUM)

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

CWE: CWE-670

Published: May 21, 2024

Last Updated: September 25, 2025

🔗 References

📤 Share & Export

📄 Export Markdown 📋 Export JSON

🔗 Related Vulnerabilities

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