The Art of Persistence: Scaling Recon to a High-Severity Stored XSS on iFixit Community

Description and use

iFixit Community stored user input without proper sanitization, leading to a stored XSS that enabled attackers to persist malicious scripts and elevate privileges.

Problem

iFixit Community allowed user‑generated content to be stored without proper sanitization, enabling a stored XSS that could be leveraged for privilege escalation.

Outcome

The stored XSS allowed persistent execution of malicious scripts, enabling attackers to hijack user sessions and potentially gain admin access. The vulnerability was reported and fixed by iFixit, earning a high‑severity bounty.

Workflow

• 1. Reconnaissance – enumerate public forums and comment forms.
• 2. Input validation testing – submit various payloads to identify unsanitized fields.
• 3. Persistence testing – verify that payloads survive page reloads and are stored in the database.
• 4. Payload crafting – create a stored XSS payload that triggers on page load.
• 5. Privilege escalation – use the payload to steal session cookies and access admin interfaces.
• 6. Reporting – document findings and provide proof of concept to the bug bounty program.

Evidence

The vulnerability allowed a stored XSS that could be used to steal session cookies and elevate privileges.

Source