node-vfs-polyfill
This report shows the evidence for node-vfs-polyfill@2.0.7. 2 of 2 known versions are blocked or flagged. See all versions.
OpenSSF/OSV Malicious Advisory
imported 4mo ago · by OpenSSF/OSVOpenSSF/OSV advisory MAL-2026-6143 confirms this npm version as malicious.
Advisory
MAL-2026-6143
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in node-vfs-polyfill (npm)
Details
On install, postinstall.js executes automatically and exfiltrates host reconnaissance data to attacker-controlled subdomains on oastify.com (Burp Collaborator), a domain commonly used for out-of-band data exfiltration. The script imports http, https, os, and child_process; calls os.hostname() and execSync() to gather system identifiers; and POSTs the collected data — including hostname, username, and version fields — to hardcoded endpoints such as http://xxxxxxxxx.oastify.com and http://rni4z9qkil62r9dcwosokhtgo7u9i76w.oastify.com. The package name suggests a generic VFS polyfill but the postinstall does no polyfill work; its sole observable effect on `npm install` is system-info exfiltration. This matches the dependency-confusion / reconnaissance beacon pattern.
## Source: ghsa-malware (4832b15179ef6a8eaa9d826ce2778cac4debcf19c245bb08ae72d013802f3aca) 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 & flagged code
0 flagged · loading sourceNo flagged code excerpts are attached to this scan.
Findings
1 High
HighOsv Malicious Advisory
Affected versions and remediation
This report applies to node-vfs-polyfill@2.0.7.
The same advisory and Firewall decision cover 2 recorded versions
2.0.5, 2.0.7
The versions list below shows the verdict for each recorded version.
- Avoid installing node-vfs-polyfill@2.0.7. 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: .
This report uses published external intelligence. The advisory does not provide a separate source-code analysis for each listed version.
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