CVE-2017-5628 : Security Advisory and Response

Artifex Software, Inc. detected a vulnerability in MuJS before version 8f62ea10a0af68e56d5c00720523ebcba13c2e6a, where the MakeDay function fails to validate the month, resulting in a numerical overflow when processing a malicious JavaScript file.

Understanding CVE-2017-5628

MuJS vulnerability impacting the MakeDay function in jsdate.c file.

What is CVE-2017-5628?

This CVE identifies a flaw in MuJS that allows an integer overflow due to improper validation of the month in the MakeDay function.

The Impact of CVE-2017-5628

The vulnerability could be exploited by an attacker to execute arbitrary code or cause a denial of service by tricking a user into opening a specially crafted JavaScript file.

Technical Details of CVE-2017-5628

Details about the vulnerability in MuJS.

Vulnerability Description

The MakeDay function in the jsdate.c file of MuJS fails to validate the month, leading to a numerical overflow when processing a malicious JavaScript file.

Affected Systems and Versions

MuJS versions before 8f62ea10a0af68e56d5c00720523ebcba13c2e6a

Exploitation Mechanism

An attacker can exploit this vulnerability by crafting a malicious JavaScript file to trigger the integer overflow.

Mitigation and Prevention

Steps to mitigate and prevent exploitation of CVE-2017-5628.

Immediate Steps to Take

Update MuJS to version 8f62ea10a0af68e56d5c00720523ebcba13c2e6a or later.
Avoid opening JavaScript files from untrusted or unknown sources.

Long-Term Security Practices

Regularly update software and libraries to patch known vulnerabilities.
Implement code reviews and security testing to catch similar issues in the development phase.

Patching and Updates

Apply patches and updates provided by MuJS to address the vulnerability.