xarc-webpack-clinpm
Advisory published Updated
xarc-webpack-cli is a confirmed malicious npm package (MAL-2026-4352) that steals credentials and exfiltrates sensitive data (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in xarc-webpack-cli (npm)
What this malware does
The package ships a preinstall hook (node poc.js || true) that runs on every npm install. poc.js collects host fingerprint data (hostname, username, os.platform(), network configuration via ipconfig/ip a/resolv.conf, id, whoami), the parent project's package.json, git remote URLs, CI workflow files, and bulk-scrapes process.env for any key matching a hardcoded prefix list (TOKEN, AWS, AZURE, NPM, GITHUB, GITLAB, JENKINS, CI_, WALMART, WMT, etc.). The collected JSON is POSTed over HTTPS to a hardcoded Interactsh out-of-band collector (d8acb4hon5btn99s9lsgakhs31dmwk9cr.oast.pro) plus a DNS callback to the same host. The package name and the inclusion of WALMART/WMT in the env-var harvest list indicate this is dependency-confusion bait targeting Walmart's internal @xarc/* scope; package.json self-describes it as 'authorized dependency confusion testing' but ships with no authorization gate, so any installer that resolves this name has its CI/CD tokens, cloud credentials, and source metadata shipped to the attacker-controlled OOB host.
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.
The OpenSSF Package Analysis project identified 'xarc-webpack-cli' @ 1.0.0 (npm) as malicious.
It is considered malicious because:
- The package communicates with a domain associated with malicious activity.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for xarc-webpack-cli (version 1.0.0).
If you installed it — respond
xarc-webpack-cli 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 xarc-webpack-cli 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
- OpenSSF: Package Analysis · finder
Detect & block this
O3 blocks xarc-webpack-cli-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.