CVE-2021-26252 : Vulnerability Insights and Analysis

A flaw was found in htmldoc version 1.9.12, where a heap buffer overflow in pspdf_prepare_page() in ps-pdf.cxx may lead to the execution of arbitrary code and denial of service.

Understanding CVE-2021-26252

This article provides insights into the CVE-2021-26252 vulnerability, its impact, technical details, and mitigation steps.

What is CVE-2021-26252?

CVE-2021-26252 is a vulnerability identified in htmldoc version 1.9.12, allowing an attacker to trigger a heap buffer overflow in pspdf_prepare_page() function, potentially leading to the execution of arbitrary code and denial of service.

The Impact of CVE-2021-26252

Exploitation of this vulnerability could result in an attacker executing arbitrary code or causing denial of service on the affected system, posing a significant risk to the security and stability of the system.

Technical Details of CVE-2021-26252

This section delves into the specific technical aspects of the CVE-2021-26252 vulnerability.

Vulnerability Description

The vulnerability arises from a heap buffer overflow in the pspdf_prepare_page() function in ps-pdf.cxx of htmldoc version 1.9.12, enabling attackers to execute arbitrary code and disrupt services.

Affected Systems and Versions

The vulnerability affects htmldoc version 1.9.12. Specifically, htmldoc 1.9.15 is confirmed as an affected version that is vulnerable to this heap buffer overflow.

Exploitation Mechanism

Malicious actors can exploit this heap buffer overflow vulnerability by crafting specific inputs to trigger the pspdf_prepare_page() function, which manipulates the memory allocated for the operation, leading to arbitrary code execution and potential service disruption.

Mitigation and Prevention

Mitigation strategies are crucial to reduce the risk posed by CVE-2021-26252 and safeguard systems from potential exploitation.

Immediate Steps to Take

Update htmldoc to a patched version that addresses the identified heap buffer overflow vulnerability.
Implement proper input validation to mitigate potential buffer overflow attacks.

Long-Term Security Practices

Regularly monitor for security updates and patches for htmldoc and other software components to address known vulnerabilities.
Conduct security assessments and audits to identify and remediate potential security weaknesses proactively.

Patching and Updates

Ensure timely application of security patches and updates for htmldoc to address vulnerabilities and enhance the overall security posture of the system.