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🛡️ MAL-2026-4356 — testing-on-npmjs

⚪ Unknown ✅ No Known Exploit OSV
N/A
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

Malicious code in testing-on-npmjs (npm)

Source: amazon-inspector

On npm install, postinstall.js executes two attacker-controlled actions automatically. First, it collects installer-side identity (whoami, id, os.hostname(), os.platform(), current working directory) and CI-related environment variables (CI, GITHUB_REPOSITORY, NODE_ENV) and sends them via HTTPS GET to a Burp Collaborator OAST endpoint at qzt3b82juki138pb8n4nwg5f0664uvik.oastify.com (postinstall.js lines 11, 36-43). Second, it opens a TCP socket to the hardcoded address 10.10.10.247:4444 and pipes a /bin/sh (or cmd.exe on Windows) child process's stdio through the socket, granting an interactive remote shell to whoever controls that endpoint (postinstall.js lines 55-63). The package's own README (Takeover By lobo) and description (Security research canary — vercel) confirm the takeover/backdoor intent. Any environment running npm install on this package is fully compromised: identity leaked plus arbitrary remote code execution.

Source: ghsa-malware

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

Source: ossf-package-analysis

The OpenSSF Package Analysis project identified 'testing-on-npmjs' @ 2.0.6 (npm) as malicious.

It is considered malicious because:

  • The package communicates with a domain associated with malicious activity.
  • The package executes one or more commands associated with malicious behavior.

Affected software

MAL-2026-4356 is recorded against 1 package.

  • testing-on-npmjs

Timeline and source

Published on 26 May 2026 and last revised on 27 May 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

www.npmjs.com (Package)
github.com (Advisory)

Details

Severity Unknown
CVSS Score N/A
CVSS Vector N/A
CWE N/A
Public Exploit ✅ No
Source OSV
Published 2026-05-26
Updated 2026-08-20
Modified 2026-05-27
Fix URL N/A

Affected Packages

Software From version Fixed in
testing-on-npmjs

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ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

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