registry / Credential exfiltration / pob-test-typescript-package-in-monorepo
pob-test-typescript-package-in-monorepo
This report shows the evidence for pob-test-typescript-package-in-monorepo@4.2.10. 17 of 17 known versions are blocked or flagged. The newest version, 4.2.17, is blocked. See all versions.
AI Security Review
scanned 3mo ago · by lpm-firewall-aiThe lifecycle hook is not package-aligned: it stages a runtime solely to execute an opaque payload absent from the normal library entrypoint. This is concrete install-time remote-code and credential-exfiltration behavior.
Static reason
One or more suspicious static signals were detected.; source matched previously finalized malicious package; routed for review; source fingerprint signature matched known malicious package; routed for review
Trigger
npm install / preinstall
Impact
Arbitrary remote code may run during installation and exfiltrate developer credentials.
Mechanism
remote payload execution with credential-token handling
Attack narrative
The preinstall hook invokes setup.mjs, which downloads a Bun binary to a temporary directory and uses it to execute the bundled, heavily obfuscated math_init.js. That payload contains network-response evaluation and GitHub-token processing behavior, creating an unconsented install-time path to remote execution and credential theft.
AI rationale
The lifecycle hook is not package-aligned: it stages a runtime solely to execute an opaque payload absent from the normal library entrypoint. This is concrete install-time remote-code and credential-exfiltration behavior.
Evidence
package.jsonsetup.mjsmath_init.jsdist/index-node18.mjs
Network endpoints1
github.com/oven-sh/bun/releases/download/bun-v1.3.13/
Decision evidence
public snapshotAI called this Malicious at 99.0% confidence as Malware with low false-positive risk.
Evidence for block
- package.json runs `node setup.mjs` at preinstall.
- setup.mjs downloads Bun then executes math_init.js during install.
- math_init.js is a 728 KB obfuscated payload, unrelated to the package’s tiny exported module.
- math_init.js dynamically evaluates code returned from a network request.
- math_init.js includes credential/token-handling paths, including GitHub-token logic.
Evidence against
- dist/index-node18.mjs only exports a greeting based on its declared dependency.
- The normal runtime entrypoint has no suspicious behavior.
Behavioral surface
ChildProcessEvalFilesystemNetworkShell
HighEntropyStringsMinifiedUrlStrings
Source & flagged code
5 flagged · loading sourcepackage.jsonView file
•scripts.preinstall = node setup.mjs
High
Install Time Lifecycle Scripts
Package defines install-time lifecycle scripts.
package.jsonView on unpkgmath_init.jsView file
1// @bun @bun-cjs
L2: var MmgoCP,etDiOOB,JqTtnbZ,bc3Kak,ZQmUTyQ,TTUgga,MDX6yrw,h8wMJNB,CabwE2L,x5ErqV;function WV8StW(MmgoCP,etDiOOB,JqTtnbZ){for(JqTtnbZ=0x0;JqTtnbZ<etDiOOB;JqTtnbZ++)MmgoCP.push(MmgoCP...
Low
Eval
Package source references a known benign dynamic code generation pattern.
math_init.jsView on unpkg · L1setup.mjsView file
1Manifest entrypoint (scripts.preinstall) carries capability families absent from dist/build output: execution+network
L1: #!/usr/bin/env node
L2: import { execFileSync } from "child_process";
L3: import _0x488df8 from "fs";
L4: import _0x52943e from "https";
L5: import _0x24db8d from "os";
...
L50: function ra() {
L51: const _0x51cd53 = process.platform + "-" + process.arch;
L52: const _0x3ab5c4 = PM[_0x51cd53];
...
L218: } else if (_0xc0d7d2 === 8) {
L219: _0x27994e = _0x548d91.inflateRawSync(_0x5975df);
L220: } else {
Findings
4 High2 Medium5 Low
HighInstall Time Lifecycle Scriptspackage.json
HighEntrypoint Build Divergencesetup.mjs
HighKnown Malware Source Similaritysetup.mjs
HighKnown Malware Source Fingerprint Signaturesetup.mjs
MediumNetwork
MediumStructural Risk Force Deep Review
LowScripts Present
LowEvalmath_init.js
LowFilesystem
LowHigh Entropy Strings
LowUrl Strings
Affected versions and remediation
This report applies to pob-test-typescript-package-in-monorepo@4.2.10.
The versions list below shows the verdict for each recorded version.
- Avoid installing pob-test-typescript-package-in-monorepo@4.2.10. 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: .
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