Thousands of Developer Credentials Stolen in macOS “s1ngularity” Attack

A supply chain attack called “s1ngularity” on Nx versions 20.9.0-21.8.0 stole thousands of developer credentials. The attack targeted macOS and AI tools, according to GitGuardian’s analysis.

A sophisticated cyberattack, dubbed the “s1ngularity” attack, has compromised Nx, a popular build platform widely used by software developers. The attack, which began on August 26, 2025, is a supply chain attack, a type of security breach where hackers sneak malicious code into a widely used piece of software, which then infects all the people who use it.

The attack was designed to steal a wide variety of sensitive data, including GitHub tokens, npm authentication keys, and SSH private keys. These credentials are essentially digital keys that provide access to a user’s accounts and systems.

The malicious software also went a step further, targeting API keys for popular AI tools like Gemini, Claude, and Q, demonstrating a new focus on emerging technologies. In addition to stealing data, the attackers installed a destructive payload that modified users’ terminal startup files, causing their terminal sessions to crash.

GitGuardian’s analysis shared with Hackread.com revealed some surprising details about the attack and its victims. The firm found that 85% of the infected systems were running macOS, highlighting the attack’s particular impact on the developer community, which frequently uses Apple computers.

In a curious turn, GitGuardian found that of the hundreds of systems where AI tools were targeted, many of the AI clients unexpectedly resisted the malicious requests. They either outright refused to run the commands or gave responses suggesting they knew they were being asked to do something wrong, showing a potential, though unintentional, new layer of security.

The stolen credentials were not only valuable but also widespread. GitGuardian’s monitoring platform, which tracks public GitHub activity, discovered 1,346 repositories used by the attackers to store stolen data.

To avoid detection, the attackers double-encoded the stolen data before uploading it. This number is far higher than the ten publicly visible repositories, as GitHub was quickly working to delete the rest. An analysis of these repositories revealed 2,349 distinct secrets, with over 1,000 still valid and working at the time of the report. The most common secrets were for GitHub and popular AI platforms.

For anyone who used the malicious Nx versions 20.9.0 through 21.8.0, the most crucial step is to immediately assume that their credentials have been exposed. GitGuardian has created a free service called HasMySecretLeaked that allows developers to check for compromised credentials without ever revealing their actual keys.

This attack reminds us that simply deleting a compromised file is not enough; the actual secret keys and tokens must be revoked and rotated to prevent further access by the attackers.