CVE-2023-36810 : What You Need to Know

A vulnerability has been discovered in the pypdf library that could allow an attacker to create a malicious PDF file triggering a long runtime issue. This CVE affects versions of pypdf prior to 1.27.9, leading to a quadratic runtime problem that consumes high CPU resources.

Understanding CVE-2023-36810

This vulnerability, identified as CVE-2023-36810, is classified under CWE-407: Inefficient Algorithmic Complexity.

What is CVE-2023-36810?

pypdf is a Python-based PDF library used for various PDF file operations such as splitting, merging, cropping, and page transformation. Attackers can exploit this vulnerability by crafting a PDF file that causes a significant increase in runtime, severely impacting system performance.

The Impact of CVE-2023-36810

The vulnerability results in a quadratic runtime issue, causing the affected process to be blocked and maxing out CPU utilization on a single core. While it does not directly affect memory usage, it can lead to system slowdowns and unresponsiveness.

Technical Details of CVE-2023-36810

The following technical details pertain to CVE-2023-36810:

Vulnerability Description

An attacker can exploit the vulnerability by creating a PDF file that triggers excessive runtimes, significantly impacting system performance and potentially leading to denial of service.

Affected Systems and Versions

The vulnerability affects versions of the pypdf library prior to 1.27.9, which do not include the necessary fix to address the quadratic runtime issue.

Exploitation Mechanism

Attackers exploit the vulnerability by crafting a PDF file that triggers unexpected runtime behavior in the pypdf library, leading to high CPU utilization.

Mitigation and Prevention

To mitigate the risks associated with CVE-2023-36810, users should take immediate action and implement the following security measures:

Immediate Steps to Take

Update to pypdf version 1.27.9 or newer, which contains the fix for the quadratic runtime vulnerability.

Long-Term Security Practices

Regularly update software libraries and dependencies to ensure vulnerabilities are addressed promptly.

Patching and Updates

Stay informed about security advisories related to the pypdf library and apply patches as soon as they are available.