MAL-2026-4356

    Dashboard / Malicious Package / MAL-2026-4356

    MAL-2026-4356

    Published: 26 May 2026Last Modified: 27 May 2026Aliases: 
    GHSA-4847-p5f9-4366

    Summary: Malicious code in testing-on-npmjs (npm)

    Details: Source: amazon-inspector (1575dee70b1f079b297d26405595aa16591e62de8fac896cf9ea485d6f534132) 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 (9aa408e186e92d2311cc7a848056ad9ae5ac9451ef65f586b6f6e70b4c3836e0) 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 (cf253783e300490b93cbf122d395cd50576ce01b2d765f75533242bbe88cff27) 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 packages

    Package

    Name: testing-on-npmjs

    Purl: pkg:npm/testing-on-npmjs

    Affected ranges

    Type: SEMVER

    Events:

    Introduced- 0
    Fixed -None

    Affected versions

    2.0.6
    2.0.5
    MAL-2026-4356 | CVE-DB