Vulnerability in Kernel: Disallow Extremely Large seq Buffer Allocations
Summary
GSD-2021-1001378: seq_file: disallow extremely large seq buffer allocations. Affects Kernel versions >= 058504edd02667eef8fac9be27ab3ea74332e9b4, < 6de9f0bf7cacc772a618699f9ed5c9f6fca58a1d. 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 crucial component of the Linux operating system, responsible for managing system resources and facilitating communication between hardware and software. It provides essential functionalities such as process management, memory management, and device drivers. The vulnerability in question affects the Kernel's seq_file module, which is responsible for handling sequential file access. Seq buffers are used to store data temporarily during sequential file operations. However, this vulnerability allows for the allocation of extremely large seq buffers, potentially leading to memory exhaustion and denial-of-service attacks.
Vulnerability Detail
The vulnerability arises from a flaw in the seq_file module, specifically in the buffer allocation mechanism. By exploiting this flaw, an attacker could request the allocation of an excessively large seq buffer, consuming a significant amount of memory resources. This could result in system instability, performance degradation, or even a complete system crash. Although the impact and attack plausibility have not been proven, it is crucial to address this vulnerability to mitigate potential risks.
How To Fix
No fixed version is published for this vulnerability.
Tip — Not sure whether your app is affected? Vulert can check the versions your app actually runs. Scan free →
Workaround
As a workaround, users can apply the patch manually by cherry-picking the commit 6de9f0bf7cacc772a618699f9ed5c9f6fca58a1d into their Kernel source code and recompiling the Kernel. Here is an example of how to apply the patch using the git cherry-pick command:
$ git cherry-pick 6de9f0bf7cacc772a618699f9ed5c9f6fca58a1d
After applying the patch, rebuild and reinstall the Kernel to ensure the fix is in effect.
Conclusion
The vulnerability in the Kernel's seq_file module, allowing for the allocation of extremely large seq buffers, poses a potential risk of memory exhaustion and denial-of-service attacks. It is crucial to update the Kernel to version v4.19.198 or later to mitigate this vulnerability. For further assistance and support in addressing this vulnerability, please contact DevNack.com.
See every vulnerability recorded for Kernel →
FAQ
The Kernel is a critical component of the Linux operating system, responsible for managing system resources and facilitating communication between hardware and software.
The seq_file module is part of the Kernel and is used for handling sequential file access. It provides an interface for reading and writing data from and to sequential files.
A seq buffer is a temporary storage area used during sequential file operations. It allows data to be read or written in a sequential manner.
Exploiting this vulnerability could lead to memory exhaustion, system instability, performance degradation, or even a complete system crash.
To fix this vulnerability, update the Linux Kernel to version v4.19.198 or later, which includes the necessary patch to prevent the allocation of extremely large seq buffers.
Related vulnerabilities
Recent vulnerabilities recorded for Kernel.
