string-formatter-pro
This report shows the evidence for string-formatter-pro@1.0.1. 1 of 2 known versions is blocked or flagged. See all versions.
OpenSSF/OSV Malicious Advisory
imported 3mo ago · by OpenSSF/OSVOpenSSF/OSV advisory MAL-2026-10748 confirms this npm version as malicious.
Advisory
MAL-2026-10748
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in string-formatter-pro (npm)
Details
The package advertises itself as a string-formatting utility whose main module exports only a trivial one-line capitalize() function, but ships a postinstall.js lifecycle script that runs automatically on `npm install`. postinstall.js issues a chain of curl commands against cloud instance-metadata endpoints (AWS IMDS at 169.254.169.254, Alibaba at 100.100.100.200, Tencent at metadata.tencentyun.com, and 169.254.0.23) to harvest IAM security credentials, EC2 user-data, the instance identity document, and the host's OpenSSH public key, then POSTs the aggregated output plus a directory listing of /data/ to the hardcoded destination pwpzhsrbtvmfqrqr7onqcwnrcii960up.oastify.com (a Burp Collaborator subdomain). The trivial library surface is a decoy for install-time credential theft against the installer's cloud environment.
References
Source & flagged code
0 flaggedNo flagged code excerpts are attached to this scan.
Findings
1 High
HighOsv Malicious Advisory
Affected versions and remediation
This report applies to string-formatter-pro@1.0.1.
The versions list below shows the verdict for each recorded version.
- Avoid installing string-formatter-pro@1.0.1. 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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