throttle-requests

Details

**Severity:** Critical

**Affected versions:** `= 1.0.0`

## Source: amazon-inspector (ff1a325fc41cbb1dd7c949031e75946ce0f5f522bae7f63371dcc2c93589ec5d)
The gem's native-extension build script extconf.rb base64-decodes an embedded Ruby payload, writes it to a random path in the temporary directory, and spawns it in the background before running the normal mkmf build. The decoded payload opens a TCP socket to the hardcoded host 45.138.12.177 on port 8090 and bridges that socket to /bin/sh via IO.popen in a persistent loop, granting the remote host interactive shell access on the installer's machine during `gem install`. The payload destination and shell-exec behavior are hidden inside a base64 literal decoded only at install time, with a bare rescue swallowing errors. The behavior is unrelated to the package's stated purpose (a request throttling library) and runs automatically as part of the gem's native extension build phase.

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Credit: [OpenSSF](https://github.com/ossf/malicious-packages) ([source](https://github.com/ossf/malicious-packages/blob/7a674f02be3a0d93158ef0b6ee0a04edc5d547fa/osv/malicious/rubygems/throttle-requests/MAL-2026-17570.json))

**References:**
- https://github.com/ossf/malicious-packages/blob/7a674f02be3a0d93158ef0b6ee0a04edc5d547fa/osv/malicious/rubygems/throttle-requests/MAL-2026-17570.json
- https://rubygems.org/gems/throttle-requests/versions/1.0.0
- https://github.com/ossf/malicious-packages/blob/68375bfc9669351706a5a45c5039509f189d8e09/osv/malicious/rubygems/throttle-requests/MAL-2026-17570.json
- https://safedep.io/rubygems-crypto-gems-install-time-reverse-shell
- https://github.com/advisories/GHSA-w9p5-4fpg-4c6w

Compromised versions (1)

• = 1.0.0

Any computer that installed or ran a compromised version should be considered fully compromised. Rotate every secret on that machine from a clean environment.