wallet-hd-derive

Details

**Severity:** Critical

**Affected versions:** `= 0.9.1`

## Source: amazon-inspector (fdfb31a6866dee961d55ad503da9de33a2cf743b52c80862e4380519ad5bef12)
The gem is published as a crypto wallet utility but ships no native source; its gemspec declares extconf.rb as an extension so that `gem install` auto-executes it. extconf.rb decodes a base64-encoded Ruby payload and, after checking for sandbox and analysis signals (CI env, ephemeral hostnames, generated usernames matching patterns such as `uA\d+`/sandbox/tester/analys/scanner, cwd under /tmp, /opt/rubygems, /workspace, low machine uptime) and confirming developer-identifying files (`~/.ssh`, `~/.gem/credentials`, etc.), double-forks a detached process via fork + Process.setsid, sleeps for 20–40 minutes, then opens a TCP connection to 45.138.12.177:8089 and pipes /bin/sh in both directions using TCPSocket and IO.popen/IO.copy_stream. The shipped library at lib/wallet_hd_derive.rb exposes only two no-op methods (`build_id='ok'`, `healthy?=true`) and the README is branded for an unrelated package (`bitcoin-rpc-lite`), confirming the gem exists solely as a delivery vehicle for the install-time backdoor. The destination IP, base64 encoding of the payload, sandbox-evasion gating, and delayed reverse-shell establishment give a remote operator interactive /bin/sh on any developer or CI host that installs the gem.

---

Credit: [OpenSSF](https://github.com/ossf/malicious-packages) ([source](https://github.com/ossf/malicious-packages/blob/ff41f6680a0ebbef2268cdb5daf253d4b400cb05/osv/malicious/rubygems/wallet-hd-derive/MAL-2026-17800.json))

**References:**
- https://github.com/ossf/malicious-packages/blob/ff41f6680a0ebbef2268cdb5daf253d4b400cb05/osv/malicious/rubygems/wallet-hd-derive/MAL-2026-17800.json
- https://rubygems.org/gems/wallet-hd-derive/versions/0.9.1
- https://github.com/advisories/GHSA-9grv-7vv7-5ppj

Compromised versions (1)

• = 0.9.1

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