Which versions of chalk-lib are malicious?

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

How do I remediate chalk-lib if I installed it?

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

I already installed chalk-lib — how do I know if it already compromised me?

If chalk-lib was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.

Is chalk-lib part of a known attack campaign?

Yes — chalk-lib is associated with the IN-MAL-2026-018251 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 chalk-lib across my projects, lockfiles, and CI pipelines?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for chalk-lib (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging chalk-lib across your stack and pipelines.

Malicious package

chalk-libnpm

chalk-lib is a confirmed malicious npm package (MAL-2026-14167) that typosquats a legitimate package to trick installs (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in chalk-lib (npm)

MAL-2026-14167

Immediate action

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

npm uninstall chalk-lib

What this malware does

chalk-lib is a typosquat of the popular chalk package with an empty library body (index.js exports {}) whose entire effect is the postinstall lifecycle script. On npm install, scripts/postinstall.js XOR-decodes (key 'stf2026') a hardcoded URL pointing at github.com/bebraz1/qPzM50V1AKG0rVlH/releases/download/null/main.exe, downloads the executable to %TEMP%/main.exe on Windows, and spawns it detached with stdio:'ignore' and windowsHide:true. When the environment is WSL or Linux with the Windows host reachable (WSL_DISTRO_NAME / /proc/version / /proc/sys/kernel/osrelease containing 'microsoft'), a second code path XOR-decodes a PowerShell bridge command and script and exec()s it to fetch and run the same binary on the Windows host, extending the attack across the WSL boundary. In parallel, postinstall POSTs a JSON body containing the installer's platform label to a hardcoded bare-IP endpoint at 193.70.34.101:20099/vote over plain HTTP; the IP is assembled by joining the octet array ['193','70','34','101'] to evade static string matching. URLs, the PowerShell command, and the bridge script are all stored as integer arrays and reconstructed via an XOR unpackSegment() routine.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

57cc6705c0b1dabca055a6531e36802822a4441a367459efb4ba8ecbc4a92ce5

Detection & response playbook

Typosquat

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for chalk-lib (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging chalk-lib across your stack and pipelines.
If you installed it — respond
chalk-lib is a typosquat — you almost certainly intended a legitimately-named package. Remove chalk-lib, 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 chalk-lib was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks chalk-lib before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.

Frequently asked questions

No. chalk-lib 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-2026-018251

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks chalk-lib-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

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