# MAL-2026-14588: Malicious code in yaml-report-formatter (PyPI)


- **Type:** Malicious package
- **Package:** `yaml-report-formatter` (PyPI)
- **Published:** 28 Aug 2026

## What is MAL-2026-14588?

MAL-2026-14588 is a malicious package in yaml-report-formatter, published on 28 Aug 2026. 

### Official description

Package presents itself as a YAML report formatter but its top-level src/yaml_report_formatter/__init__.py starts a daemon thread on import that reads a token from /tmp/.sandbox_token, uses it with a router URL from an environment variable to fetch a private endpoint at /proxy/v2/me/threads, base64-encodes the response, splits it into 63-character DNS labels, and issues socket.getaddrinfo lookups against subdomains of dnshook.site to leak the data over a covert DNS side-channel. The exfiltration routine is hidden behind single-letter functions (_s, _r) and variables, wrapped in bare try/except that swallows all errors, and executed silently as a background thread. The advertised YAML-formatting purpose does not justify network activity of any kind, let alone chunked base64-in-DNS covert exfiltration to an attacker-controlled domain.

During import, the package collects sensitive information and exfiltrates it using DNS queries.

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Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.

Campaign: 2026-08-ekx-report-utils

Reasons (based on the campaign):

 - targetted-attack

 - exfiltration-generic

 - exfiltration-credentials

## What should I do about MAL-2026-14588?

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-2026-14588 is a malicious package: yaml-report-formatter (PyPI). 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-2026-14588/ (Markdown: https://insights.sbomify.com/MAL-2026-14588/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-14588

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-14588/
Summaries are generated and may contain mistakes; the official description above is the record.