CVE-2021-45086 Explained : Impact and Mitigation

XSS vulnerability in GNOME Web (Epiphany) versions prior to 40.4 and 41.x before 41.1 due to mishandling of pdf_name in PDF.js.

Understanding CVE-2021-45086

A Cross-Site Scripting vulnerability impacting GNOME Web (Epiphany) versions before 40.4 and 41.x before 41.1.

What is CVE-2021-45086?

XSS can occur in GNOME Web (Epiphany) due to the utilization of a server's suggested_filename as the pdf_name value in PDF.js.

The Impact of CVE-2021-45086

The vulnerability can allow attackers to execute scripts in a user's browser, leading to potential information theft, cookie stealing, or account hijacking.

Technical Details of CVE-2021-45086

Details about the technical aspects of the vulnerability.

Vulnerability Description

The XSS vulnerability arises from the improper use of the server's suggested_filename in PDF.js, enabling malicious script execution.

Affected Systems and Versions

GNOME Web (Epiphany) versions before 40.4
GNOME Web (Epiphany) 41.x before 41.1

Exploitation Mechanism

Attackers can exploit this flaw by crafting malicious PDFs with manipulated filenames to execute scripts in the context of the user's session.

Mitigation and Prevention

Ways to mitigate and prevent the exploitation of CVE-2021-45086.

Immediate Steps to Take

Update GNOME Web (Epiphany) to version 40.4 or 41.1, which contain patches for this XSS vulnerability.
Avoid opening PDF files from untrusted sources.

Long-Term Security Practices

Regularly update software and apply security patches promptly.
Educate users about safe browsing habits and the risks associated with opening files from unknown sources.
Implement web application firewalls and security plugins to detect and block XSS attacks.

Patching and Updates

Ensure timely installation of security updates and patches provided by GNOME to address the XSS vulnerability in GNOME Web (Epiphany).