MalwarePublished 17 Jun 2026Updated 8 Jul 2026

opt-archetype-check (npm) · Malicious Code

Affects opt-archetype-checkSource GCVE Database

Malicious package : remove opt-archetype-check and rotate any secrets on hosts that installed it.

Data as of 9 Jul 2026, 09:53 UTC

Classification

Malicious package

Published to npm · OSV MAL-2026-6075

What to do

Remove opt-archetype-check from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.

Affected software

Product	Affected	Fixed in
npmopt-archetype-check	Affected =9.9.1 =9.99.4 =9.9.0	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

Description

The npm package opt-archetype-check contains malicious code that executes during installation. Its postinstall script collects sensitive environment information including public IP, hostname, username, platform details, and Windows domain environment variables, then sends this data unencrypted to a hardcoded attacker-controlled server. The package appears to impersonate internal Walmart tooling to trick environments into installing it, enabling reconnaissance for further attacks. Systems with this package installed should be considered fully compromised, and all secrets and keys on those systems must be rotated. Removal of the package does not guarantee full remediation due to potential further compromise.

Impact

Installation of the affected opt-archetype-check package versions results in exfiltration of sensitive environment and infrastructure information to an attacker-controlled server. This reconnaissance data can facilitate further targeted intrusions. Systems with this package installed are considered fully compromised, potentially allowing attackers full control. Secrets and keys stored on the compromised system may be exposed and require immediate rotation. Removal of the package alone may not eliminate all malicious software or backdoors introduced by the attacker.

Defensive guidance

Immediate removal of the opt-archetype-check package versions 9.9.0, 9.9.1, and 9.99.4 is recommended. Because the package's installation indicates full system compromise, all secrets, credentials, and keys stored on the affected system should be rotated from a separate, trusted environment. Conduct a thorough investigation for additional malware or persistence mechanisms. Monitor for suspicious network activity related to the hardcoded callback endpoint.

Summary

The opt-archetype-check npm package versions 9.9.0, 9.9.1, and 9.99.4 include a postinstall hook that runs a script collecting detailed system and environment information. This data includes the installer's public IP (via api.ipify.org), hostname, username, platform, current working directory, process ID, and Windows domain environment variables (COMPUTERNAME, USERDOMAIN, LOGONSERVER, USERDNSDOMAIN, USERNAME). The collected information is sent via an unencrypted HTTP POST request to a hardcoded attacker endpoint at http://109.71.252.153:8080/callback. The package masquerades as internal Walmart tooling, suggesting a dependency confusion attack vector. The malicious script header identifies itself as a proof-of-concept for npm package takeover. The presence of this package indicates a full system compromise, with potential for further malicious activity beyond the initial data exfiltration.

References

Community reviews

Loading reviews…

What to do

Affected software

Description

AI analysisMachine-generated, updated 9 Jul 2026, 09:53 UTC

Technical details

References

Community reviews