Microsoft-owned code hosting platform GitHub says the recent cyberattack that resulted in the cloning of private repositories was highly targeted in nature.
Disclosed in mid-April, the incident involved stolen OAuth tokens issued to third-party integrators Heroku and Travis CI, which were used to download the private repositories of dozens of organizations.
The two continuous integration (CI) systems help organizations automate the scanning of newly introduced code changes, to help identify vulnerabilities and malicious snippets before they enter production.
These systems use authentication tokens to facilitate the automaton process, and the recent cyberattack happened after such tokens were compromised.
The tokens are not stored by GitHub in their original format, meaning that a threat actor obtaining them would not be able to abuse them in attacks, the platform says.
Using the stolen tokens, the attackers authenticated to the GitHub API and then listed all of the organizations for all accounts they could access. Next, the attackers selected targets of interest and proceeded to list and download their private repositories.
After analyzing the attackers’ behavior, GitHub concluded that they were listing organizations solely with the purpose of identifying accounts and private repositories to clone.
“GitHub believes these attacks were highly targeted based on the available information and our analysis of the attacker behavior using the compromised OAuth tokens issued to Travis CI and Heroku,” the code hosting platform notes.
GitHub also says it is now in the process of sending the final set of notifications to the users/organizations impacted in the attack, but encourages users to monitor Heroku and Travis CI for future updates on the matter.
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