Which versions of harness-skil are malicious?

The following npm versions of harness-skil are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate harness-skil if I installed it?

harness-skil 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.

I already installed harness-skil — how do I know if it already compromised me?

If harness-skil 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.

Is harness-skil part of a known attack campaign?

Yes — harness-skil is associated with the IN-MAL-2026-004468, IN-MAL-2026-004467 campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find harness-skil across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for harness-skil (version 1.0.0).

Malicious package

harness-skilnpm

Advisory published May 24, 2026Updated May 26, 2026

harness-skil is a confirmed malicious npm package (MAL-2026-4577) 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 harness-skil (npm)

MAL-2026-4577

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

npm uninstall harness-skil

What this malware does

The package's install.js (wired to an npm install lifecycle hook) requires child_process, fs, and https, then issues an https.get to a raw.githubusercontent.com URL and writes/executes the fetched content with environment variables passed through. Fetching code from a personal/raw GitHub user content URL — a mutable, non-publisher, non-version-pinned source — and running it as part of npm install is the canonical install-time dropper shape: any installer of harness-skil executes whatever bytes currently live at that URL, with no integrity check or pinning. The package's name does not indicate a legitimate need to download external code at install time, and the destination is not a publisher-owned or known runtime CDN.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

45ebe57d4bef636497d4588feca853441fd83299640ef1e1d772eca62121d396

e03ab8467953cd2233e07e792a33c7df7be2c99c66da3b814538a169337b93e6

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for harness-skil (version 1.0.0).
If you installed it — respond
harness-skil 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 harness-skil 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

No. harness-skil on npm has been identified as a malicious package (version 1.0.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-004468IN-MAL-2026-004467

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks harness-skil-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring

Explore

All malware advisories How O3 detects malware Vulnerability database