## Critical JWT Token Security Flaw Exposes Web Application to XSS and CSRF Attacks
A high-severity security vulnerability has been identified in a web application's authentication system, where improperly configured JWT tokens lack essential security flags, leaving them exposed to token theft and session hijacking. The flaw resides in the `auth.ts` file, where tokens are set in cookies without the `HttpOnly`, `Secure`, and `SameSite` flags, creating a direct path for attackers to exploit.

The current vulnerable implementation uses `document.cookie` to set the token, making it accessible to client-side JavaScript. This absence of the `HttpOnly` flag opens the door to Cross-Site Scripting (XSS) attacks, where malicious scripts could steal the token. Furthermore, weak or missing `SameSite` settings fail to provide adequate protection against Cross-Site Request Forgery (CSRF) attacks, allowing unauthorized cross-site requests. The lack of the `Secure` flag also risks exposure over unencrypted HTTP connections, facilitating man-in-the-middle attacks.

The recommended fix mandates implementing a secure cookie configuration with all critical flags: `httpOnly: true` to block JavaScript access, `secure: true` to enforce HTTPS-only transmission, and `sameSite: 'strict'` for robust CSRF protection. This configuration, combined with a sensible expiration time, is essential to mitigate the immediate risks of session compromise and unauthorized access. The vulnerability underscores a critical oversight in basic web security hygiene that could have widespread implications for user data integrity and application trust.
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- **Source**: GitHub Issues
- **Sector**: The Lab
- **Tags**: JWT, Security Vulnerability, XSS, CSRF, Authentication
- **Credibility**: unverified
- **Published**: 2026-03-26 20:27:23
- **ID**: 36058
- **URL**: https://whisperx.ai/en/intel/36058