Possible Github URL Check Bypass Leads to Github Token Leak

[aydinnyunus]

Vulnerability Description: The vulnerability allows attackers to bypass security checks and obtain GitHub tokens of users by spoofing GitHub URLs. The vulnerability lies in the code snippet provided:

• https://github.com/sunholo-data/sunholo-py/blob/e715dcc8a32edcf910f03c787f517b18ca02334a/sunholo/chunker/data_to_embed_pubsub.py#L47

elif message_data.startswith("https://github.com"):
    chunks, metadata = handle_github_message(message_data, metadata, vector_name)

The code appears to handle messages containing URLs starting with "https://github.com". However, it lacks proper validation to ensure that the URL belongs to GitHub and is not spoofed.

Impact:

• Unauthorized access to GitHub tokens: The attacker gains access to GitHub tokens of users, potentially compromising their GitHub accounts.
• Data Breach: Access to GitHub tokens may lead to unauthorized access to sensitive repositories, code, and data stored on GitHub.
• Account Takeover: With access to GitHub tokens, the attacker can perform actions on behalf of the compromised user, including pushing malicious code, modifying repositories, and accessing private information.

Recommendations for Mitigation:

1. URL Validation: Implement robust URL validation techniques to ensure that URLs belong to legitimate domains and are not spoofed.
2. GitHub Token Security: Avoid exposing GitHub tokens in URLs or messages whenever possible. Instead, use secure authentication methods such as OAuth tokens with proper authorization scopes.
3. Input Sanitization: Sanitize and validate all user-provided inputs, including URLs, to prevent injection attacks and spoofing attempts.
4. Security Awareness: Educate developers about the risks of URL spoofing and the importance of secure coding practices to prevent such vulnerabilities.

[MarkEdmondson1234]

Hmm thank you, but this is all a server side process so I'm not sure how the URL tokens would then be accessed by an end user, but I will look at validation nevertheless. Is there a recommended way to do this?

[aydinnyunus]

Hi,

I am not sure about the input part this is why I use "Possible" in title. If there is a doubt, you can use url parsing libraries to get the domain part and check the domain is whatever you need.