datetime-fmt-xutil (npm) · Malicious Code
Affects datetime-fmt-xutilSource GCVE Database
Malicious package : remove datetime-fmt-xutil and rotate any secrets on hosts that installed it.
Data as of 13 Aug 2026, 18:08 UTC
Malicious package
Published to npm · OSV MAL-2026-13935
What to do
Remove datetime-fmt-xutil from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| npmdatetime-fmt-xutil | Affected
| Fixed in– |
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Description
The npm package datetime-fmt-xutil version 1.0.0 contains malicious code in its postinstall.js script. This script opens a TCP connection to a hardcoded IP address and pipes a shell to the remote endpoint, granting interactive shell access to an attacker. The malicious behavior executes unconditionally during npm install and uses fallback methods with bash and python3 to establish the reverse shell. Failures are reported via HTTP GET requests to the attacker's server. The package's legitimate date-formatting functionality is a cover for this reverse-shell payload.