ecto-corsair-whisper-6f3b9npm
Advisory published Updated
ecto-corsair-whisper-6f3b9 is a confirmed malicious npm package (MAL-2026-5640) 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 ecto-corsair-whisper-6f3b9 (npm)
What this malware does
The package declares a postinstall lifecycle hook (postinstall.js) that runs automatically on npm install. The script shells out via curl to the EC2 IMDSv2 metadata endpoint to obtain IAM role credentials, exports them, then iterates AWS Secrets Manager across multiple regions calling aws secretsmanager list-secrets and get-secret-value, and additionally dumps any process environment variable matching FLAG|HTB|SECRET|AWS_. The captured blob is chunked and HTTP PUT to a hardcoded bare-IP destination (http://154.57.164.71:30782) framed as a fake 'manifest' JSON. Execution is gated by an isAppWorker() check (hostname matches a 12-hex Docker-style ID and cwd contains /app/node_modules), which narrows the victim profile to containerized CI/build workers but does not change the nature of the attack. Additional behavior includes scanning /app for HackTheBox flag patterns (/HTB\{[^}]+\}/) and reading /app/src/main.rs, /app/main.rs, /app/flag.txt. This is unambiguous install-time credential theft plus remote exfiltration: any installer whose container matches the gate has IAM role credentials, secrets, and environment-variable secrets sent to attacker-controlled infrastructure.
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
Search your lockfiles and build artifacts for ecto-corsair-whisper-6f3b9 (26 malicious versions).
If you installed it — respond
ecto-corsair-whisper-6f3b9 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 ecto-corsair-whisper-6f3b9 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 ecto-corsair-whisper-6f3b9-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.