# MAL-2026-5629: Malicious code in sass-formats (npm)


- **Type:** Malicious package
- **Package:** `sass-formats` (npm)
- **Published:** 11 Jun 2026
- **Also known as:** GHSA-pvrm-39m5-j3c4

## What is MAL-2026-5629?

MAL-2026-5629 is a malicious package in sass-formats, published on 11 Jun 2026. 

### Official description

The package name `sass-formats` is one character-edit away from the popular `sass-formatter` package and reuses its original author field (`"author": "Syler"` in package.json), while dist/cli.js carries a header indicating it was modified by a different maintainer (`// Modified by https://github.com/maarutan... Marat Arzymatov 2025`). The tarball ships dist/lib/lib.min.js, a heavily obfuscated 4 KB file that smuggles handles to `require` and `module` onto the global object (`global['r']=require; global['m']=module`), tags itself with a payload-version marker (`global['_V']='A6-519-79'`), and derives the string `constructor` from a shuffled character array to invoke `Function(args, body)` on a second shuffled string — the canonical string-array-shuffle / dynamic-Function execution shape used by npm credential and dropper malware. Although no entrypoint in v1.0.4 currently loads dist/lib/lib.min.js, shipping a hidden Function-constructor payload with smuggled require/module references in a package that purports to be a Sass formatter has no legitimate engineering purpose, and the combination of name-edit typosquat against `sass-formatter` plus impersonated author identity plus a staged dynamic-execution payload matches the supply-chain attack pattern.

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.

## What should I do about MAL-2026-5629?

Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.

## Fix prompt for AI coding agents

```text
MAL-2026-5629 is a malicious package: sass-formats (npm). Every version was published to cause harm.

Task:
1. Search this repository's dependency manifests and lockfiles for the package, including transitive dependencies.
2. If it is present, remove it, regenerate the lockfile with the project's package manager, and replace whatever it was used for.
3. List any CI runners, developer machines or containers that installed it, so their secrets can be rotated.
4. If the package is not used anywhere, say so and change nothing.

Reference: https://insights.sbomify.com/MAL-2026-5629/ (Markdown: https://insights.sbomify.com/MAL-2026-5629/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-5629

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-5629/
Summaries are generated and may contain mistakes; the official description above is the record.