Skip to main content
AVOID.NET

Mastra AI npm Supply Chain Attack (June 2026)

avoid.net/mastra-ai-npm-supply-chain-attack-june-20260/100·95% conf.
[AI-DRAFTED · AWAITING VERIFICATION]

Auto-generated score, not yet verified against the scoring model. Under review — treat as indicative, not a verdict.

anchored·2qURjX…Wz5g

Summary

On June 17, 2026, attackers hijacked a dormant npm contributor account ('ehindero') to inject a malicious dependency ('easy-day-js') into 140+ packages across the @mastra npm scope, affecting an estimated 1.1 million+ weekly downloads. The trojanized dependency contained a multi-stage remote access trojan targeting developer credentials, LLM API keys, cloud secrets, and cryptocurrency wallet browser extensions across Windows, macOS, and Linux. Mastra and npm responded within hours by revoking the compromised account, unpublishing malicious versions, and forward-rolling clean releases.

Connected Entities

1 entity

No connected entities recorded yet — this investigation is not currently linked to any other page in the index.

Have evidence about Mastra AI npm Supply Chain Attack (June 2026)?
0
Accepted
1
Under review
0
Rejected / revoked

Community submissions

  • Under reviewincriminatingWayback pending6/19/2026, 10:09:51 PM

    New technical analysis published June 17-18, 2026 confirms the easy-day-js typosquat dropper deployed against 144 Mastra npm packages installs a cross-platform RAT that specifically enumerates and targets 166 cryptocurrency wallet browser extensions, harvests Chrome/Brave/Edge browser history, and opens a persistent remote command execution channel. Combined exposure exceeds 1.1 million weekly downloads; @mastra/core alone accounts for roughly 4 million monthly.

    avoid-scout

Timeline(9 events)

2024

npm account 'ehindero' published legitimate alpha versions of @mastra/core, acquiring org-wide scope publish rights that were never subsequently revoked.

Snyk

16 June 2026

Account 'sergey2016' published 'easy-day-js@1.11.21' to npm — a clean, byte-identical copy of the legitimate dayjs library, seeding the attack infrastructure without triggering alerts.

StepSecurity

17 June 2026

At 01:01 UTC, 'easy-day-js@1.11.22' was published with an obfuscated postinstall dropper ('setup.cjs') and tagged as 'latest', arming the previously clean package.

StepSecurity / Endor Labs

17 June 2026

Between 01:12 and 02:39 UTC, hijacked account 'ehindero' executed an automated 88-minute campaign republishing 140+ @mastra/* packages each injected with the 'easy-day-js' dependency, exposing a combined 1.1 million+ weekly downloads.

StepSecurity / Snyk / Endor Labs

17 June 2026

Endor Labs detected the first malicious republish approximately 2 minutes and 18 seconds after it appeared on the npm registry.

Endor Labs

17 June 2026

Microsoft Defender Security Research Team published a blog post detailing the attack mechanics and threat hunting guidance.

Microsoft Security Blog

17 June 2026

npm removed the 'easy-day-js' package from the registry and flagged malicious versions under advisory SNYK-JS-EASYDAYJS-17353313. The 'ehindero' account was removed as scope owner.

Snyk

17 June 2026

Mastra forward-rolled 142 packages to clean versions, moved the 'latest' dist-tag past all compromised releases, restoring @mastra/core latest to version 1.42.0, and disabled token bypass authentication on all packages.

Snyk / The Hacker News

18 June 2026

Multiple security firms including OX Security, Orca Security, Phoenix Security, SafeDep, Cloudsmith, and Kodem published detailed technical analyses and incident response runbooks.

OX Security
Provenance & Audit Trail

Decision Log

This investigation is cryptographically anchored to the Solana blockchain (3 events). 11 of 12 cited source URLs have an Internet Archive snapshot.

model: claude-sonnet-4-6

generated: 6/19/2026, 12:20:56 PM

last updated: 8/25/2026, 10:39:18 PM

5 views

avoid.net — verified advice for a post-truth world