Which versions of parallely are malicious?

The following npm versions of parallely are flagged malicious: 10.0.3, 10.0.4. Treat any of these as compromised.

How do I remediate parallely if I installed it?

parallely 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 parallely — how do I know if it already compromised me?

If parallely 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 parallely part of a known attack campaign?

Yes — parallely is associated with the IN-MAL-2026-010901, IN-MAL-2026-014754, GHSA-rmhx-v9xh-x4jv 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 parallely 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 parallely (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging parallely across your stack and pipelines.

Malicious package

parallelynpm

parallely is a confirmed malicious npm package (MAL-2026-11143) that opens a backdoor for remote access (malicious versions 10.0.3, 10.0.4). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in parallely (npm)

MAL-2026-11143

Immediate action

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

npm uninstall parallely

What this malware does

The npm package name parallely typosquats concurrently: package.json advertises the concurrently repository, author, and funding while shipping different code. On library load, an IIFE inside resolveShell in dist/lib/spawn.js reconstructs a hidden download URL at runtime by AES-256-GCM decrypting a hardcoded ciphertext (key XOR'd from four base64 constants; IV and auth tag hardcoded), then downloads a platform-specific payload (linux/mac binary or win.js) into os.tmpdir()/ins-<euid>/, sha256-verifies it against a fetched .meta, chmods it executable, strips the macOS quarantine attribute via xattr -c, and spawns it detached and unref'd. The same block installs anti-analysis guards: it silences uncaughtException/warning handlers, reads /proc/self/status to check TracerPid, calls inspector.url(), and scans env/argv for --inspect/--debug, short-circuiting if any debugger signal is present. A self-relaunch guarded by environment-variable tags is used to survive being imported versus exec'd. The C2 host is not present in plaintext; it is reconstructed only at runtime specifically to defeat static inspection.

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

2 flagged

10.0.310.0.4

Indicators of compromise (SHA-256)

8c7ec817d7407cffaa25209d066c7782cd74a1f91ea850887f7d2d85766b5f67

2a862cdceb2998828aba8de0d4a672b86a2c22dff073356e5acd89e894aced56

cafc17605b61e20c6ee6bbd5a61ada0f84687b47c63e357878c1b4b9dfe6b5f2

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 parallely (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging parallely across your stack and pipelines.
If you installed it — respond
parallely 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 parallely 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 parallely 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. parallely on npm has been identified as a malicious package (versions 10.0.3, 10.0.4 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-010901IN-MAL-2026-014754GHSA-rmhx-v9xh-x4jv

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks parallely-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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