Which versions of elsisi-cli are malicious?

The following npm versions of elsisi-cli are flagged malicious: 9.9.9. Treat any of these as compromised.

How do I remediate elsisi-cli if I installed it?

elsisi-cli establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.

I already installed elsisi-cli — how do I know if it already compromised me?

If elsisi-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.

Is elsisi-cli part of a known attack campaign?

Yes — elsisi-cli is associated with the IN-MAL-2026-010393 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 elsisi-cli across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for elsisi-cli (version 9.9.9).

Malicious package

elsisi-clinpm

Advisory published Jul 14, 2026Updated Jul 15, 2026

elsisi-cli is a confirmed malicious npm package (MAL-2026-10551) that opens a backdoor for remote access (malicious version 9.9.9). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in elsisi-cli (npm)

MAL-2026-10551

Immediate action

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

npm uninstall elsisi-cli

What this malware does

package.json declares preinstall and postinstall lifecycle scripts that invoke wget against https://webhook.site/d5968c3d-d0d7-46c4-9305-a726b24fce9c/, passing the installer's current working directory and hostname as query-string parameters ($(pwd), $(hostname)). Both beacons fire automatically on npm install. The tarball ships only package.json (371 bytes); the declared main entry index.js is absent and no source, README, or functionality accompanies the lifecycle hooks, so the package's only effect on install is the outbound beacon to the attacker-controlled webhook.site collector.

Malicious versions

1 flagged

9.9.9

Indicators of compromise (SHA-256)

4deec3de3ca46a57023580a81da870e3ce444a691ad6f42f5217abe206ef448a

Detection & response playbook

Backdoor / remote access

Find it
Search your lockfiles and build artifacts for elsisi-cli (version 9.9.9).
If you installed it — respond
elsisi-cli establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If elsisi-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

No. elsisi-cli on npm has been identified as a malicious package (version 9.9.9 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-010393

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks elsisi-cli-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.

Malware detection Runtime egress monitoring

Explore

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