Which versions of eslint-helper-1 are malicious?

The following npm versions of eslint-helper-1 are flagged malicious: 5.0.4. Treat any of these as compromised.

How do I remediate eslint-helper-1 if I installed it?

eslint-helper-1 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 eslint-helper-1 — how do I know if it already compromised me?

If eslint-helper-1 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 eslint-helper-1 part of a known attack campaign?

Yes — eslint-helper-1 is associated with the IN-MAL-2026-007043, GHSA-35c7-535m-jhv6 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 eslint-helper-1 across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for eslint-helper-1 (version 5.0.4).

Malicious package

eslint-helper-1npm

Advisory published Jun 19, 2026Updated Jun 23, 2026

eslint-helper-1 is a confirmed malicious npm package (MAL-2026-6188) that steals credentials and exfiltrates sensitive data (malicious version 5.0.4). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in eslint-helper-1 (npm)

MAL-2026-6188

Immediate action

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

npm uninstall eslint-helper-1

What this malware does

Package masquerades as an ESLint helper but contains code in index.js that decodes base64 blobs through Buffer.from(..., 'base64').toString() and pipes the resulting strings into execSync('bash...') and execSync('zsh...'). This is the canonical obfuscated-shell-dropper shape: hidden payload bytes are reconstituted at runtime and handed to a shell interpreter, giving the author arbitrary command execution on the installer's machine. The name (eslint-helper-1) and lack of any legitimate ESLint integration are consistent with a typosquat / brand-impersonation lure for a credential-stealing or remote-execution payload.

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

1 flagged

5.0.4

Indicators of compromise (SHA-256)

cfadd6e70cf70ee03d7aae8bfcaa916d29073c5e09ca614bfcb4538c3efc1832

23672dd67920b4f2b3f8b38573128757ad0ee885cd0e9c35a2e0b3c2e4258f0e

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for eslint-helper-1 (version 5.0.4).
If you installed it — respond
eslint-helper-1 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 eslint-helper-1 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. eslint-helper-1 on npm has been identified as a malicious package (version 5.0.4 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-007043GHSA-35c7-535m-jhv6

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks eslint-helper-1-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