CVE-2017-1000424 in Electron
Summary
by MITRE
Github Electron version 1.6.4 - 1.6.11 and 1.7.0 - 1.7.5 is vulnerable to a URL Spoofing problem when opening PDFs in PDFium resulting loading arbitrary PDFs that a hacker can control.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 01/19/2023
The vulnerability identified as CVE-2017-1000424 affects GitHub Electron applications running versions 1.6.4 through 1.6.11 and 1.7.0 through 1.7.5, presenting a significant URL spoofing issue within the PDF rendering component known as PDFium. This flaw allows attackers to manipulate the display of PDF documents in a manner that can deceive users into believing they are viewing legitimate content while actually loading malicious files from attacker-controlled servers. The vulnerability stems from improper handling of URL schemes and protocols when PDF documents are opened within Electron applications, creating a path for man-in-the-middle attacks and phishing attempts that can lead to unauthorized data access or system compromise.
The technical implementation of this vulnerability lies within the PDFium rendering engine integration within Electron's browser window handling mechanism. When Electron applications attempt to open PDF files through PDFium, the system fails to properly validate or sanitize the URLs associated with embedded resources within the PDF document. This allows attackers to craft PDF files containing malicious URLs in their metadata or embedded links that appear legitimate to users but actually point to attacker-controlled domains. The flaw specifically impacts how Electron processes PDF content when the application is configured to automatically open PDF files rather than prompting users for download decisions. This creates an attack surface where users can be tricked into loading PDFs from untrusted sources while the application's security context appears to be maintaining the original domain's trust relationship.
The operational impact of CVE-2017-1000424 extends beyond simple document viewing manipulation, as it can facilitate more sophisticated attacks including credential theft, malware delivery, and privilege escalation within the application's security boundaries. Attackers can exploit this vulnerability by hosting malicious PDF files on compromised or malicious websites that appear to be legitimate sources, such as banking institutions or government portals. When users open these documents within Electron applications, the system may load additional resources from attacker-controlled domains, potentially bypassing normal security restrictions. This vulnerability aligns with CWE-601 URL Redirection to Untrusted Site Attack, where the application's handling of URL resolution creates opportunities for attackers to redirect users to malicious destinations. The flaw also maps to ATT&CK technique T1193, which involves using malicious documents to gain initial access, as the PDF spoofing creates a vector for delivering additional malicious payloads or conducting phishing attacks.
Organizations utilizing Electron applications that process PDF documents must implement immediate mitigations to address this vulnerability. The most effective approach involves updating to Electron versions 1.6.12 and 1.7.6 or later, which contain patches specifically designed to address URL validation issues within PDFium integration. Additionally, application developers should implement explicit URL validation checks before opening PDF files, particularly when these documents contain embedded links or external references. Security measures should include implementing Content Security Policy headers that restrict external resource loading and configuring proper sandboxing for PDF rendering components. Organizations should also consider implementing user education programs to raise awareness about suspicious PDF files and the importance of verifying document sources before opening them. Network-level controls such as web application firewalls and URL filtering systems can provide additional protection layers, though these should not be relied upon as the sole defense mechanism. The vulnerability demonstrates the importance of maintaining up-to-date dependencies and implementing comprehensive security testing for third-party components, particularly those handling user-supplied content or external resources.