It turns out that cyber-threat actors can do quite a bit of damage with nothing more than an email address.
New research from Aikido Security published today examines how a GitLab incoming email address acts as a highly privileged access token that grants broad user rights to an organization's public and private projects. GitLab automatically assigns each user of the DevOps platform a private email address to create issues in their software projects; if a user emails the address, a new issue will appear in a project authored by that user.
Creating project issues via emails sent to automated unique addresses is not an uncommon capability, Aikido noted in the report. For example, project management platforms such as Trello, Todoist, and Monday.com have similar features.
But GitLab email addresses each contain a non-expiring token that provides broad access to an organization's resources — and not just the project in which an individual user is working. And if that address itself is publicly exposed, an attacker could abuse it for supply chain attacks without needing actual access to the account.
"Any mailbox on the internet can send to that address, and GitLab processes the message as the token's owner," the report stated. "If you have the address, you have both authentication and authorization."
Aikido's research team argues that many GitLab users are likely unaware of the risks associated with these addresses, shown by the number of intentionally exposed addresses on the public Internet.