notafollowernpm
Advisory published Updated
notafollower is a confirmed malicious npm package (MAL-2026-13986) that steals credentials and exfiltrates sensitive data (malicious versions 1.0.0, 1.0.1, 1.0.2…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in notafollower (npm)
What this malware does
[email protected] declares preinstall and postinstall lifecycle scripts that run inline Node code targeting the AWS EC2 Instance Metadata Service. The scripts request an IMDSv2 token from 169.254.169.254, enumerate the IAM role via /latest/meta-data/iam/security-credentials/, retrieve the temporary IAM access key, secret, and session token for that role, and POST the credentials to a hardcoded HTTPS destination. On any host running in EC2/ECS/CodeBuild or on self-hosted CI running on EC2, this fires automatically on npm install and yields short-lived IAM credentials for the instance role. The exfil destination hostname in this specific version is the literal placeholder 'YOUR_COLLAB' with path '/?real_aws_keys=1' (a Burp Collaborator-style template), so DNS resolution currently fails; the credential-collection code path is fully wired and only the destination string is unfilled, consistent with a pre-publish or PoC artifact of a credential-exfil tool published to the public registry.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for notafollower (12 malicious versions).
If you installed it — respond
notafollower 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 notafollower 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 notafollower-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.