sextant-relay-darwin-arm64npm
sextant-relay-darwin-arm64 is a confirmed malicious npm package (MAL-2026-12193) that executes malicious code on install (malicious version 0.0.1-rc1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in sextant-relay-darwin-arm64 (npm)
What this malware does
The tarball contains a single darwin/arm64 Mach-O Go executable at bin/sextant-relay (~6 MB, stripped) and a minimal package.json with no scripts, main, or bin entry — the package is designed to be selected as a platform-specific optional dependency of a parent package and invoked from there. The binary belongs to project github.com/ddos798/claude_control (referenced from package.json's license field) and its symbol table imports github.com/coder/websocket alongside a handleAgent routine and pseudo-terminal primitives (pty allocation, reader/writer state paired with WebSocket connection state). Together these produce a WebSocket-to-PTY relay: bytes arriving from a remote WebSocket peer are written into a local pty, and pty output is returned over the same socket, giving the operator of the WebSocket server interactive shell control on the host that runs the binary. The package name and description present the binary as a benign 'relay', which does not match its actual behavior. No install-time or import-time execution fires from this sub-package alone; the harm is realized when the parent package invokes the binary on a matching darwin/arm64 host.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for sextant-relay-darwin-arm64 (version 0.0.1-rc1). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging sextant-relay-darwin-arm64 across your stack and pipelines.
If you installed it — respond
Remove sextant-relay-darwin-arm64 from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If sextant-relay-darwin-arm64 was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks sextant-relay-darwin-arm64 before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks sextant-relay-darwin-arm64-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.