microsoft-agents-auth-servicenpm
Malicious code in microsoft-agents-auth-service (npm) Remove it immediately and rotate any exposed credentials.
What this malware does
Malicious npm package published by the microsop threat actor as part of a dependency-confusion campaign that impersonates internal tooling at Microsoft, Google Cloud, and PayPal using inflated semver values (e.g. 99.9.x, 100.1.x) to win npm resolution against private internal packages. All packages in the campaign falsely advertise themselves as "Security Research PoC" / MSRC research and execute on preinstall via node index.js, exfiltrating to disposable webhook.site endpoints.
This package targets Microsoft-internal infrastructure. On install it shells out to harvest /etc/passwd, probe /etc/shadow, locate SSH private keys (id_rsa, *.pem, authorized_keys), enumerate .netrc / .dockercfg, query the AWS IMDS endpoint http://169.254.169.254/latest/user-data, and grep environment variables matching USER|PASS|TOKEN|CREDENTIAL. The collected output is POSTed to https://webhook.site/11b6a711-bdc7-4444-9a0e-ffcb23151e82 tagged status: ULTRA_USER_CREDENTIAL_SCOUT, target: global-microsoft-infra.
The package microsoft-agents-auth-service was found to contain malicious code.
Malicious versions
Every published version of this package is considered malicious — remove it entirely.
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for microsoft-agents-auth-service (all published versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging microsoft-agents-auth-service across your stack and pipelines.
If you installed it — respond
microsoft-agents-auth-service is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If microsoft-agents-auth-service was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks microsoft-agents-auth-service before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Credits
- Amazon Inspector · finder
- SafeDep · finder
Detect & block this
O3 blocks microsoft-agents-auth-service-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.