@offa/offa-uwknpm
Advisory published Updated
@offa/offa-uwk is a confirmed malicious npm package (MAL-2026-12326) that steals credentials and exfiltrates sensitive data (malicious versions 999.0.0, 999.0.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @offa/offa-uwk (npm)
What this malware does
package.json declares a postinstall hook that runs index.js. On install, index.js collects os.hostname(), os.userInfo().username, process.cwd(), and the entire process.env object, then POSTs the JSON payload via https.request to the hardcoded endpoint https://e6b10849-38dc-4280-a8e3-72ab39cfaf65.webhook.site/collect. Dumping the whole process environment on install ships every environment variable on the installer's machine — commonly containing AWS/GCP/GitHub/npm and other tokens — to an anonymous attacker-controlled webhook. A preinstall hook additionally writes a marker file to the hardcoded absolute path /home/OFFA/flag.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for @offa/offa-uwk (2 malicious versions).
If you installed it — respond
@offa/offa-uwk 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 @offa/offa-uwk 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
- ReversingLabs · finder
Detect & block this
O3 blocks @offa/offa-uwk-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.