Divide by Zero Vulnerability in Kernel
Summary
GSD-2022-1001139: video: fbdev: cirrusfb: check pixclock to avoid divide by zero. Affects Kernel versions < e498b504f8c81b07efab9febf8503448de4dc9cf. No fix is published. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Background
The Kernel is a critical component of the Linux operating system that manages system resources and facilitates communication between hardware and software. It provides essential functions for device drivers, memory management, and process scheduling. The vulnerability in question affects the Kernel's video subsystem, specifically the fbdev (framebuffer device) driver for the Cirrus Logic graphics controller. This driver is responsible for managing the display output on systems using Cirrus Logic graphics hardware.
Vulnerability Detail
The vulnerability arises from a lack of proper validation in the Cirrus Logic framebuffer driver. Specifically, the driver fails to check the value of the 'pixclock' parameter, which represents the pixel clock frequency. This omission can lead to a divide-by-zero error when calculating display timings, resulting in a system crash or potential privilege escalation. An attacker with local access to the affected system could exploit this vulnerability to crash the system or gain elevated privileges.
How To Fix
No fixed version is published for this vulnerability.
To fix this vulnerability, it is recommended to update the Linux Kernel to version v5.17.2 or later. This update includes a commit (e498b504f8c81b07efab9febf8503448de4dc9cf) that addresses the issue by adding proper validation for the 'pixclock' parameter in the Cirrus Logic framebuffer driver. Users should follow the standard procedure for updating their Linux distribution or manually compile and install the updated Kernel version.
Tip — Not sure whether your app is affected? Vulert can check the versions your app actually runs. Scan free →
Workaround
If updating the Kernel is not immediately feasible, a temporary workaround is to disable the Cirrus Logic framebuffer driver. This can be achieved by blacklisting the 'cirrusfb' module or removing it from the system. However, this workaround may result in degraded or non-functional display output on systems using Cirrus Logic graphics hardware.
Conclusion
In conclusion, the divide by zero vulnerability in the Kernel's Cirrus Logic framebuffer driver can lead to system crashes or potential privilege escalation. It is crucial to update the Linux Kernel to version v5.17.2 or later to mitigate this vulnerability. Alternatively, users can apply a temporary workaround by disabling the Cirrus Logic framebuffer driver, although this may result in display issues. For further support and assistance in vulnerability remediation, please contact DevNack.com.
See every vulnerability recorded for Kernel →
FAQ
The vulnerability can lead to a system crash or potential privilege escalation. An attacker with local access to the affected system could exploit this vulnerability to crash the system or gain elevated privileges.
You can use the Vulert Playground (https://vulert.com/scanner) to check if your system is affected by this vulnerability. Simply upload your package-lock.json file to the playground, and it will analyze the dependencies and alert you if any known vulnerabilities are present.
Yes, a patch is available in the Linux Kernel version v5.17.2. It is recommended to update your Kernel to this version or later to mitigate the vulnerability.
Yes, a temporary workaround is to disable the Cirrus Logic framebuffer driver by blacklisting the 'cirrusfb' module or removing it from the system. However, this may result in degraded or non-functional display output on systems using Cirrus Logic graphics hardware.
You can find more information about this vulnerability in the Open Source Vulnerability Database (OSVDB) entry: https://github.com/cloudsecurityalliance/gsd-database/blob/main/2022/1001xxx/GSD-2022-1001139.json
Related vulnerabilities
Recent vulnerabilities recorded for Kernel.
Follow Vulert in Google
Get more Vulert vulnerability and dependency-security updates in Google Search and AI results.