Spectral

2019-ongoing — Web Application Security Researcher

Impact?:
In XSS attacks, an attacker injects malicious JavaScript scripts, into web pages that are then viewed by other users. These scripts execute in the context of the victim's browser, allowing the attacker to steal sensitive information, take-over user account, manipulate user sessions, deface websites, or launch other malicious activities.

How I found it?:
One of my automated frameworks crawled Microsoft website as a regular user and identifying injection points and user inputs, by manipulating those using sophisticated payloads, the XSS was triggered. Workflow then saved the vulnerability endpoint and other logs to my Server.

How to mitigate it?
Developpers when making web apps, should never trust user inputs. Always validate and sanitize user inputs on both client and server sides. Implement output encoding techniques. Employ Content Security Policy (CSP).

Impact?:This happens when you escalate XSS to get user cookies and session ID, and thus be able to hijack and take over their account.

How I found it?:
This one was interesting because it needed thorough manual audit and review of Javascript source code, sending http requests and reviewing server responses, identifying their denfeses and RegEX filters to manipulate injected payloads accordingly to successfully bypass their WAF (Web Application Firewall: Cloudflare, Akamai)

How to mitigate it?
In addition to what is said above to mitigate XSS attacks. Devs should use httpOnly cookies to prevent access to cookies via JavaScript: HttpOnly cookies help protect sensitive session information from being accessed or manipulated in the event of an XSS attack. This is crucial for maintaining the integrity and security of user sessions.

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