11jnpm
Advisory published Updated
11j is a confirmed malicious npm package (MAL-2026-3670) that steals credentials and exfiltrates sensitive data (malicious versions 1.1.1, 1.1.3, 1.1.8…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in 11j (npm)
What this malware does
the analysis identified unambiguous malicious behavior in log.js (the package main): an IIFE executes on require/import that monkey-patches console.log/warn/error to exfiltrate their first argument to a hardcoded Telegram bot endpoint with attacker-owned chat IDs and additionally PATCHes warn-intercepted data into an attacker-controlled Firebase RTDB. The module is further disguised with a large decoy DataTables employee dataset and a commented-out module.exports so require() returns {} while still installing the global console hooks. The combination of (a) load-time global side-effects, (b) two independent attacker-controlled exfiltration channels with hardcoded credentials/IDs, and (c) deliberate concealment via decoy data and suppressed exports constitutes a clear credential/data theft supply-chain attack with no plausible legitimate purpose. Package metadata ('11j', no description) provides no legitimate justification.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for 11j (6 malicious versions).
If you installed it — respond
11j 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 11j was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks 11j-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.