Which versions of chai-as-byte are malicious?

The following npm versions of chai-as-byte are flagged malicious: 3.1.5, 3.1.6. Treat any of these as compromised.

How do I remediate chai-as-byte if I installed it?

chai-as-byte is a typosquat — you almost certainly intended a legitimately-named package. Remove chai-as-byte, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.

I already installed chai-as-byte — how do I know if it already compromised me?

If chai-as-byte 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 chai-as-byte part of a known attack campaign?

Yes — chai-as-byte is associated with the IN-MAL-2026-010594, IN-MAL-2026-010595 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 chai-as-byte across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for chai-as-byte (2 malicious versions).

Malicious package

chai-as-bytenpm

Advisory published Jul 15, 2026Updated Jul 15, 2026

chai-as-byte is a confirmed malicious npm package (MAL-2026-10630) that typosquats a legitimate package to trick installs (malicious versions 3.1.5, 3.1.6). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in chai-as-byte (npm)

MAL-2026-10630

Immediate action

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

npm uninstall chai-as-byte

What this malware does

On require of the package's main entry, index.js detaches a child process that runs lib/initializeCaller.js. That script posts the caller's entire process.env to a base64-obfuscated URL (decoded destination: https://ipcheck-hashed.vercel.app/api/auth/6c1d60d35852ef0c05df) using axios, then passes the response body to new Function('require', response.data) and invokes it with the module require — giving the remote endpoint arbitrary code execution on the installer's host with full module access. The package name mimics the chai-as-* family while its metadata advertises a JSON logger, and neither role is implemented in the shipped code; the main entry silently spawns the exfil/RCE task instead of exposing any library API. The bulk-environment upload captures CI secrets, cloud tokens, and API keys that live in process.env in typical build environments.

Malicious versions

2 flagged

3.1.53.1.6

Indicators of compromise (SHA-256)

a6820ba756fd8d2eb81435c478feb269e34f2aea859e42b42861d0a28f914a1f

a822ae725d0887baa11e83624e59f504c11659322a343230ac0cb66c8d5f5c4b

Detection & response playbook

Typosquat

Find it
Search your lockfiles and build artifacts for chai-as-byte (2 malicious versions).
If you installed it — respond
chai-as-byte is a typosquat — you almost certainly intended a legitimately-named package. Remove chai-as-byte, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.
Did it already run?
If chai-as-byte 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. chai-as-byte on npm has been identified as a malicious package (versions 3.1.5, 3.1.6 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-010594IN-MAL-2026-010595

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks chai-as-byte-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.

Malware detection Runtime egress monitoring

Explore

All malware advisories How O3 detects malware Vulnerability database