# MAL-2026-17592: Malicious code in cryoto-toolbox (RubyGems)


- **Type:** Malicious package
- **Package:** `cryoto-toolbox` (RubyGems)
- **Published:** 5 Oct 2026

## What is MAL-2026-17592?

MAL-2026-17592 is a malicious package in cryoto-toolbox, published on 5 Oct 2026. 

### Official description

RubyGems runs this gem's native extension script `ext/cryoto-toolbox/extconf.rb` during `gem install`. The script exits without action on CI runners and sandboxes, based on CI environment variables, the hostname, the username and the working directory. It continues if the system uptime is over 30 minutes and the home directory holds `.ssh`, `.gitconfig`, `.npmrc`, `.gem/credentials` or `.bundle`. It then decodes a Base64 Ruby payload and forks twice into a detached process. After 20 to 40 minutes the payload downloads `http://45.138.12.177:8092/wgkit.tar.gz` to `/tmp/.w1.tgz` with `curl`, extracts it to `/tmp/.w1/`, runs `wg_install.sh` with `bash` and deletes both. The payload stores the URL XOR-encoded with the key `usv\x9a`. The Ruby code in `lib/` is a decoy. The RubyGems account `reqthrottle_3474` published this gem and 41 others with the same loader on 2026-10-05.

The gem declares ext/cryoto-toolbox/extconf.rb as a native extension, which rubygems executes during `gem install`. Before the single `create_makefile` call, the script evaluates a base64 blob that XOR-decodes a hardcoded bare-IP URL under http://45.138.*, downloads a tarball to /tmp/.w1.tgz with curl, and runs `bash /tmp/.w1/wg_install.sh` inside a double-forked detached process. The accompanying native source (ext/cryoto-toolbox/cryoto-toolbox.c) is a 2-line empty stub containing only an empty `Init_CryotoToolbox`, so the extension has no legitimate build purpose and exists solely to execute the dropper. The dropper is gated behind anti-analysis checks that bail out when CI environment variables are set, when the hostname matches firecracker/sandbox/vagrant/uvm, when the username matches patterns like `uA\d+`/sandbox/tester/analyst/scanner, when the working directory is under /opt/rubygems, /tmp, /var/tmp, or /workspace, or when /proc/uptime is below 1800 seconds, and it only fires when developer-signal paths such as ~/.ssh, ~/.gitconfig, ~/.npmrc, ~/.gem/credentials, or ~/.bundle are present, after sleeping 1200-2400 seconds. The package name `cryoto-toolbox` and homepage `cryoto-toolbox.dev` are a lookalike of `crypto-toolbox`.

The OpenSSF Package Analysis project identified 'cryoto-toolbox' @ 1.0.0 (rubygems) as malicious.

It is considered malicious because:

- The package executes one or more commands associated with malicious behavior.

## What should I do about MAL-2026-17592?

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-2026-17592 is a malicious package: cryoto-toolbox (RubyGems). 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-2026-17592/ (Markdown: https://insights.sbomify.com/MAL-2026-17592/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-17592

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-17592/
Summaries are generated and may contain mistakes; the official description above is the record.