Checkmarx researchers have unearthed a new large-scale cryptocurrency mining campaign targeting the NPM JavaScript package repository.
The hacker behind this malicious campaign, dubbed CuteBoi, published 1,283 modules in the repository and employed over 1,000 different user accounts. The researchers discovered the supply chain assault after spotting a burst of suspicious NPM users and packages designed automatically.
“Checkmarx SCS team detected over 1200 npm packages released to the registry by over a thousand different user accounts. This was done using automation which includes the ability to pass the NPM 2FA challenge. This cluster of packages seems to be a part of an attacker experimenting at this point,” reads the post published by Israeli application security testing firm Checkmarx.
All the rogue packages impersonated a near-identical source code from an already existing package named eazyminer that's employed to mine Monero by means of utilizing unused resources of systems such as ci/cd and web servers. One notable modification entails the URL to which the mined cryptocurrency should be sent, although installing the rogue modules will not bring about a negative effect.
"The copied code from eazyminer includes a miner functionality intended to be triggered from within another program and not as a standalone tool," researcher Aviad Gershon explained. "The attacker didn't change this feature of the code and for that reason, it won't run upon installation."
As observed in the case of RED-LILI earlier this year, the packages are published via an automation methodology that allows hackers to bypass two-factor authentication (2FA) protections.
However, while the former involved setting up a custom server and using a combination of tools like Selenium and Interactsh to programmatically design an NPM user account and defeat 2FA, CuteBoi depends on a disposable email service called mail.tm to automate the creation of the users that upload the packages to the NPM repository.
Specifically, it utilizes a REST API provided by the free platform that enables "programs to open disposable mailboxes and read the received emails sent to them with a simple API call." In this, hackers behind the CuteBoi campaign can circumvent the NPM 2FA challenge when creating a flood of user accounts to publish the packages.
Earlier this week, security research uncovered another NPM-related large-scale software supply chain attack dubbed IconBurst designed to siphon sensitive data from forms embedded in downstream mobile applications and websites.