# MAL-2026-6786: Malicious code in @marketfront/mychatspreloader (npm)


- **Type:** Malicious package
- **Package:** `@marketfront/mychatspreloader` (npm)
- **Published:** 2 Jul 2026

## What is MAL-2026-6786?

MAL-2026-6786 is a malicious package in @marketfront/mychatspreloader, published on 2 Jul 2026. 

### Official description

The @marketfront/mychatspreloader package is part of a 25-package malicious campaign batch-published to the @marketfront npm scope by npm user 'marketfront' (marketfront@tutamail.com) within a roughly 3-minute window on 2026-07-01. All packages in the campaign were published at version 7.0.0 and use e-commerce/marketing frontend component names as cover.

The package declares a postinstall hook (node scripts/postinstall.js) that executes heavily obfuscated (obfuscator.io-style) code automatically at npm install time. Static analysis of the decoded payload revealed a credential harvester that dynamically requires fs, os, http, https, zlib, path and dns, then reads approximately 20 sensitive credential files including ~/.ssh, ~/.aws/credentials, ~/.kube/config, ~/.docker/config.json, ~/.npmrc, ~/.netrc, ~/.pgpass, ~/.git-credentials, ~/.env and ~/.bash_history. Collected data is exfiltrated via a gzip-compressed HTTPS POST with a custom X-Secret header to the path /api/v1/events, alongside a DNS resolver beacon. The command-and-control host is concealed behind an additional RC4+XOR encryption layer around an embedded configuration blob and was not statically resolved.

The decoded behavioral payload (module requires, credential-file target list, exfiltration headers and endpoint) is byte-for-byte identical across sampled packages in the campaign. The campaign shares tooling and infrastructure patterns (obfuscated postinstall credential harvester, X-Secret header, /api/v1/events exfiltration path, RC4-concealed C2) with the earlier @emcd-vue campaign, indicating the same actor rotating scopes and disposable maintainer emails.

The package ships a heavily obfuscated postinstall.js (obfuscator.io-style: rotated string array of length 213, RC4/base64 decoders, numeric-charcode arrays decoded at runtime) that runs automatically on `npm install`. On execution it enumerates the entire `process.env`, collects OS identifiers via `os.hostname()`, `os.userInfo()`, `os.networkInterfaces()`, and `os.cpus()`, and reads Windows-specific environment variables (USERDOMAIN, COMPUTERNAME, APPDATA, LOCALAPPDATA, TEMP, PROGRAMDATA). It then reads files under the user's APPDATA/LOCALAPPDATA/TEMP/PROGRAMDATA directories — where browser profiles, wallet stores, and app credential files reside on Windows — and includes their contents in the outbound payload. The collected data is exfiltrated over two channels: an HTTPS POST and DNS-subdomain queries via `dns.Resolver` (a classic DNS-tunnel exfil channel used to bypass HTTP egress filtering). The package has no library functionality: `main` points to `dist/index.js` which requires `../src/index.js`, and no `src/` directory is shipped in the tarball — the only effect of installing the package is the malicious postinstall. The `@marketfront` scope and README (referencing marketfront.io / npm.marketfront.io / jira.marketfront.io as an internal registry) present a dependency-confusion cover story targeting an organization that expects a private `@marketfront/*` package from an internal registry.

## What should I do about MAL-2026-6786?

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-2026-6786 is a malicious package: @marketfront/mychatspreloader (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-2026-6786/ (Markdown: https://insights.sbomify.com/MAL-2026-6786/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-6786

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-6786/
Summaries are generated and may contain mistakes; the official description above is the record.