Security vulnerabilities

  • Status Closed
  • Assigned To
    nferrari
  • Private
Attached to Project: Security vulnerabilities
Opened by nhlimon - 18.10.2025
Last edited by nferrari - 28.10.2025

FS#230 - Bug Bounty Report: Lack of Proof-of-Possession (PoP) in Access Tokens

Summary:
The OAuth implementation relies solely on bearer tokens (RFC 6750). Bearer tokens act like “keys to the kingdom” — anyone holding them gets full access. Without Proof-of-Possession (PoP) or sender-constrained tokens, a stolen token can be reused by an attacker from any device, IP, or session.

Steps to Reproduce:

Log in to the alwaysdata.com application and obtain a valid bearer access token (e.g., via browser dev tools).

Replay the same token from a completely different environment:

Another browser,

Another machine,

Or a proxy/intercepting tool.

Observe that the API/service still accepts the token without verifying the device, TLS channel, or binding key.

Impact:

Token Replay Attacks: Stolen tokens from XSS, CSRF, or insecure storage can be reused by attackers.

Session Hijacking: An attacker can impersonate users indefinitely until the token expires/revoked.

High-Severity Risk: Any token leak = full account compromise.

Closed by  nferrari
28.10.2025 11:39
Reason for closing:  Invalid
Admin

Hi,

Please provide a demonstration.

Loading...

Available keyboard shortcuts

Tasklist

Task Details

Task Editing