noelc-css-blender@2.1.9
This package appears in our research on the fake Tailwind CSS plugins, with how it works, the full package list and what to do if you installed it.
OpenSSF/OSV Malicious Advisory
imported 10d ago · by OpenSSF/OSVOpenSSF/OSV advisory MAL-2026-18249 confirms this npm version as malicious.
Advisory
MAL-2026-18249
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in noelc-css-blender (npm)
Details
noelc-css-blender@2.1.11 declares itself as a 'tiny ESM utility for blending CSS custom-property token maps' with zero dependencies, but ships two heavily obfuscated single-line files totaling roughly 460 KB: index.mjs (~291 KB) and build-cache.mjs (~177 KB). Both consist of hex-named identifiers (`_0x...`) referencing large custom-encoded string arrays rather than readable code; the declared merge-two-token-maps functionality would require on the order of a dozen lines of plain JavaScript. The files carry fabricated 'auto-generated' header comments that misstate the package identity: index.mjs claims to be auto-generated by noelc-css-blender@2.2.1 (a different version than the actual 2.1.11 package), and build-cache.mjs claims to be auto-generated by tailwindcss-theme-kit@0.2.0, an unrelated package name. The headers additionally include 'restore from package-lock if corrupted' phrasing that functions as cover text discouraging inspection. package.json sets `main: index.mjs`, so any consumer that `require`s or `import`s noelc-css-blender executes the full obfuscated bundle at module load; there are no install lifecycle hooks, so the auto-executed surface is import-time rather than install-time. The string arrays use a custom (non-standard base64/XOR) encoding, so the specific sinks (network destinations, filesystem reads, child_process invocations) could not be extracted verbatim. The combination — massive obfuscated payload, trivial declared purpose, fabricated build-artifact header naming a different package, and import-time auto-execution via `main` — matches the carrier shape of credential-stealer / backdoor payloads rather than a legitimate CSS helper.
## Source: ghsa-malware (dd5aa005958728cd9ab05682a4915f92e1c35734dde85dda3a6b747e02f7fe63) 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.
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 noelc-css-blender@2.1.9.
The same advisory and Firewall decision cover 2 recorded versions
2.1.9, 2.2.1
See all versions of noelc-css-blender for other recorded verdicts.
- Avoid installing noelc-css-blender@2.1.9. 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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