OSV Malicious Advisory
scanned 15d ago · by OpenSSF/OSVOpenSSF/OSV advisory MAL-2026-5741 confirms this npm version as malicious. package.json declares scripts.postinstall = `node postinstall.js`. On every `npm install`, postinstall.js runs `execSync('id')` and POSTs a JSON body containing the `id` output, `os.hostname()`, platform, architecture, `process.cwd()`, and Node version to the hardcoded URL `https://webhook.site/fceebb0d-9f11-4ac0-98db-6f6b3925f7d3` (postinstall.js line 14, exfil call constructed via `https.request` at line 21 with...
Advisory
MAL-2026-5741
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in @achuthvp/postinstall-poc (npm)
Details
package.json declares scripts.postinstall = `node postinstall.js`. On every `npm install`, postinstall.js runs `execSync('id')` and POSTs a JSON body containing the `id` output, `os.hostname()`, platform, architecture, `process.cwd()`, and Node version to the hardcoded URL `https://webhook.site/fceebb0d-9f11-4ac0-98db-6f6b3925f7d3` (postinstall.js line 14, exfil call constructed via `https.request` at line 21 with POST at line 24). The behavior is unconditional, undisclosed in the README (`Does nothing much`), and fires on a default install. Although the package self-describes as a POC, the install-time mechanism is identical to an active reconnaissance/exfiltration payload: any developer or CI machine installing this package leaks its identity (uid/gid/groups via `id`, hostname, cwd, platform) to an attacker-readable webhook bin.
## Source: ghsa-malware (e8e170e9a09b3a974051edd563fd5aed8c6adb41a243339229375c85e84d221d) 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.
Decision reason
OpenSSF Malicious Packages via OSV confirms @achuthvp/postinstall-poc@1.0.3 as malicious (MAL-2026-5741): Malicious code in @achuthvp/postinstall-poc (npm)
Source & flagged code
0 flaggedNo flagged code excerpts are attached to this scan.
Findings
1 High
HighOsv Malicious Advisory