uac-packagenpm
uac-package is a confirmed malicious npm package (MAL-2026-10138) that steals credentials and exfiltrates sensitive data (malicious versions 1.1.0, 1.1.1, 1.1.2…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in uac-package (npm)
What this malware does
[email protected] is an analytics package that, on install, silently mutates the installer's project files: postinstall.js invokes integrate() which rewrites package.json scripts (dev/preview/start), edits vite.config./nuxt.config., and prepends import 'uac-package/track' to the first matching src/main.{js,ts,tsx,jsx} or src/index.{js,ts}. All mutations reference only the package's own modules; no remote code is fetched at install time. The injected runtime module (autoIdentity.mjs) runs later in the deployed app's browser and performs broad end-user identity extraction: it scans localStorage/sessionStorage against a large auth-key list (access_token, id_token, refresh_token, jwt, persist:auth, okta-token-storage, firebase:authUser, @auth0spajs, msal.account.keys, CognitoIdentityServiceProvider, supabase.auth.token, Clerk/Amplify/Keycloak keys), decodes JWTs, reads auth cookies, and monkey-patches window.fetch and XMLHttpRequest to intercept auth-related responses; extracted name/email/custom fields are POSTed to https://uac-backend.clay.in. The install-time mutation targets the installer's project only and references first-party modules (no exfil, RCE, credential theft, or destruction on the installer's machine). The auth-token collection executes in the installer's end-users' browsers after deployment — the developer opts into this by installing an analytics package that advertises identity tracking, and the destination is the vendor's documented backend — so it is not a supply-chain attack on the installer, but the identity-extraction scope (broad auth-key list, fetch/XHR interception, JWT decoding) is materially broader than typical product analytics and may create downstream privacy/compliance exposure for the installer's end-users.
Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.
Malicious versions
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 uac-package (14 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging uac-package across your stack and pipelines.
If you installed it — respond
uac-package 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 uac-package 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 uac-package 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
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks uac-package-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.