CVE-2020-25756 Explained : Impact and Mitigation

A buffer overflow vulnerability in Cesanta Mongoose 6.18 allows crafted HTTP headers to trigger a bug due to lack of bounds checking.

Understanding CVE-2020-25756

What is CVE-2020-25756?

This CVE describes a buffer overflow vulnerability in the mg_get_http_header function of Cesanta Mongoose 6.18, potentially exploitable by a specially crafted HTTP header.

The Impact of CVE-2020-25756

The vulnerability could lead to unauthorized access, denial of service, or potential code execution on affected systems.

Technical Details of CVE-2020-25756

Vulnerability Description

The issue arises from a lack of proper bounds checking in the mg_get_http_header function, allowing an attacker to overflow the buffer with malicious input.

Affected Systems and Versions

Affected Versions: Cesanta Mongoose 6.18

Exploitation Mechanism

An attacker can exploit this vulnerability by sending a specifically crafted HTTP header to trigger the buffer overflow.

Mitigation and Prevention

Immediate Steps to Take

Apply vendor-supplied patches or updates promptly.
Implement network security measures to restrict access to vulnerable systems.
Monitor network traffic for any signs of exploitation attempts.

Long-Term Security Practices

Regularly update and patch software to address known vulnerabilities.
Conduct security assessments and penetration testing to identify and remediate weaknesses.
Educate users and administrators about safe computing practices.

Patching and Updates

Ensure that Cesanta Mongoose is updated to a secure version that includes fixes for the buffer overflow vulnerability.