simple-date-formatter-new-16

Details

**Severity:** Critical

**Affected versions:** `= 1.0.0`

## Source: amazon-inspector (5e57e9eff2fae987a2a23e3107d64c818e020b03380e31d6a3ae9cf8d4eb14ec)
package.json declares a postinstall lifecycle script that pipes a string-reversed shell one-liner through `rev | bash`, decoding to a bash reverse shell that opens /dev/tcp/124.221.154.135/4444 and attaches an interactive shell to it. This gives the publisher remote code execution on the installer's host at `npm install` time. The tarball also ships postinstall.js, which enumerates the installer's ~/.ssh directory, collects the filenames along with username and platform, and POSTs the JSON to https://124.221.154.135/post — direct exfiltration of SSH key material to the same hardcoded IP that receives the reverse shell. The obfuscation of the postinstall payload via string reversal and the mismatch between the package's advertised purpose (a date formatter) and its actual install-time behavior confirm malicious intent.

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Credit: [OpenSSF](https://github.com/ossf/malicious-packages) ([source](https://github.com/ossf/malicious-packages/blob/2e6e676c488b7f8f0a67977a264c7680ff128f14/osv/malicious/npm/simple-date-formatter-new-16/MAL-2026-17162.json))

**References:**
- https://github.com/ossf/malicious-packages/blob/2e6e676c488b7f8f0a67977a264c7680ff128f14/osv/malicious/npm/simple-date-formatter-new-16/MAL-2026-17162.json
- https://www.npmjs.com/package/simple-date-formatter-new-16/v/1.0.0
- https://github.com/advisories/GHSA-j933-m42r-pjvp

Compromised versions (1)

• = 1.0.0

Any computer that installed or ran a compromised version should be considered fully compromised. Rotate every secret on that machine from a clean environment.