The recent Nx "s1ngularity" NPM supply chain attack has led to a massive security fallout, exposing thousands of account tokens and repository secrets, according to Wiz researchers.
A post-incident analysis revealed that the breach compromised 2,180 accounts and 7,200 repositories in three distinct attack phases. Wiz emphasized that the impact is still unfolding, as many of the leaked secrets remain valid.
Nx, a widely used open-source build system and monorepo management tool in enterprise-scale JavaScript/TypeScript projects, has over 5.5 million weekly downloads on the NPM registry.
How the Attack Happened
On August 26, 2025, threat actors exploited a flawed GitHub Actions workflow in the Nx repository. This enabled them to publish a malicious version of Nx on NPM containing a post-install malware script called telemetry.js.
The telemetry.js malware targeted Linux and macOS systems, attempting to steal sensitive data such as GitHub tokens, npm tokens, SSH keys, .env files, and even crypto wallets. The stolen data was then uploaded to public repositories under the name "s1ngularity-repository."
What made this breach particularly unique was the attacker’s use of AI command-line tools like Claude, Q, and Gemini. These tools were leveraged with changing LLM prompts to hunt for and extract secrets.
"The evolution of the prompt shows the attacker exploring prompt tuning rapidly throughout the attack. We can see the introduction of role-prompting, as well as varying levels of specificity on techniques," explained Wiz.
"These changes had a concrete impact on the success of the malware. The introduction of the phrase ‘penetration testing’, for example, was concretely reflected in LLM refusals to engage in such activity."
Three Phases of the Attack
Phase 1 (Aug 26–27): Backdoored Nx packages impacted around 1,700 users, leaking more than 2,000 unique secrets and exposing 20,000 files from infected systems. GitHub removed attacker-created repositories within eight hours, but the stolen data had already been duplicated.
Phase 2 (Aug 28–29): Using stolen GitHub tokens, attackers flipped private repositories to public, renaming them with the “s1ngularity” tag. This compromised 480 more accounts (mostly organizations) and exposed 6,700 private repositories.
Phase 3 (from Aug 31): The attackers focused on a single organization, using two compromised accounts to publish another 500 private repositories.
Root Cause & Response
The Nx team later confirmed that the breach stemmed from a pull request title injection combined with insecure use of pull_request_target. This flaw allowed attackers to execute arbitrary code with elevated permissions, triggering Nx’s publish pipeline and stealing the npm publishing token.
In response, Nx revoked compromised tokens, adopted two-factor authentication, and migrated to NPM’s Trusted Publisher model, which eliminates token-based publishing. Additionally, manual approvals are now required for pull request-triggered workflows.