GitHub Breached With the use of Stolen Tokens

Digital criminals have breached dozens of repositories used on GitHub. The attack was performed with stolen tokens. The tokens in question are “OAuth” tokens. Let’s take a closer look at the details of the digital attack.

When did GitHub Find out About the Attack?

GitHub launched its analysis of the stolen tokens in the second week of April. At this time, GitHub’s security team initially determined there was an unauthorized access to its node package management (NPM) infrastructure. The unauthorized access occurred with the use of API keys obtained by the hackers after downloading private NPM repositories. NPM is best described as a tool used to publish or download node packages.

What has GitHub Revealed About the Attack?

To GitHub’s credit, the company has shared a detailed timeline of the digital security breaches that occurred throughout the previous month. The timeline specifies all the information pertaining to when the digital miscreants obtained access to its repositories. Those repositories belonged to more than a dozen different private parties.  

GitHub representatives have stated that stolen OAuth tokens allowed for sensitive data to be taken from the repositories. However, GitHub’s public relations team insists it does not believe the digital thieves obtained the tokens by overcoming GitHub’s digital security defenses. The company does not store the OAuth tokens in original formats that are considered functional. The attack details were highlighted by GitHub’s chief security officer, Mike Hanley.

What Does OAuth Mean?

The OAuth tokens are Open Authorization tokens. OAuth is a protocol or framework for standard authorization that allows for authorization that is based on tokens on the web. OAuth empowers third parties to use certain account information relating to end-users. It must be noted that OAuth does not allow for the sharing of user credentials. Rather, OAuth relies on authorization tokens for users to prove their identity and then functions as a middleman to authorize applications functioning in unison with other applications.  

It must be noted incidents involving found or stolen OAuth tokens obtained by malicious parties are more common than most assume. As an example, readers will find it interesting to learn that Microsoft endured an OAuth weakness in the winter of 2021. Its applications ranging from Office 365 to Microsoft Trust Service, were susceptible to authentication problems that allowed digital miscreants to obtain control over Azure accounts.

How Does OAuth Abuse Occur?

The abuse using OAuth tokens requires that the malevolent party initially register the harmful app in the framework of the OAuth provider. The redirection URL is used to direct toward the phishing site. At this point, the digital miscreant transmits the phishing message to the target, including the URL for authorization of the OAuth.

What Does GitHub’s Analysis of the Attack Reveal?

According to GitHub representatives, the company’s internal analysis of the digital security breach reveals the digital criminals authenticated to the company’s API with pilfered OAuth tokens. The tokens in question were issued to Travis CI and Heroku accounts. The company states most of the OAuth apps affected were within the GitHub accounts. The attacks are also characterized as highly selective. The digital miscreants copied private repositories for targeting. This approach reveals the attackers selectively targeted specific repositories.

What is GitHub’s Response to the Attack?

GitHub states it is in the process of transmitting notifications of the attack to the affected parties. All GitHub clients with the Heroku or Travis CI OAuth apps within their accounts with the company will be notified of the attack.