On August 4, 2026, attackers compromised the maintainer accounts of the widely used npm packages keyv and cacheable, publishing trojanized versions containing a preinstall hook that downloads a standalone Bun runtime and runs obfuscated second-stage code. This code harvests AWS instance metadata, cloud keys, Vault tokens, Kubernetes service-account tokens, GitHub Actions secrets, npm tokens, and other private keys or bearer tokens found on disk. Using stolen npm tokens, the payload propagates by injecting the malicious hook into other packages it can publish, creating a worm that rapidly expanded to over 440 packages and 2000+ versions. The attack also installs a host-level dead-man's switch as a macOS LaunchAgent or Linux systemd user service that monitors the validity of stolen GitHub tokens. If a token is revoked (causing an HTTP 4xx response), the switch executes a remote attacker-controlled handler, then self-destructs. This design punishes the typical remediation step of immediate token revocation. The attack vector includes execution triggered by opening the source repository in IDEs or AI coding agents, not just by running npm install. The recommended incident response is to isolate the host from the network first, preserve evidence, eradicate the malware and persistence, then rotate and revoke credentials in the prescribed order to avoid triggering the dead-man's switch.

The compromise allows attackers to steal a wide range of sensitive credentials including cloud keys, GitHub tokens, npm tokens, Vault tokens, Kubernetes tokens, and private keys from affected hosts. The worm-like propagation mechanism enables rapid spread across thousands of npm package versions, increasing the attack surface. The dead-man's switch mechanism can trigger unknown malicious actions remotely if stolen GitHub tokens are revoked prematurely, potentially causing data destruction or re-implantation. The attack vector includes execution without explicit installation, increasing the risk of unnoticed compromise. The incident can affect build hosts, developer machines, CI runners, and any system that clones or opens affected repositories. The complexity and stealth of the attack complicate detection and remediation.

The vendor advisory and analysis recommend first isolating affected hosts from the network to prevent the dead-man's switch from triggering. Do not power off the host to preserve volatile evidence. Collect and preserve files related to the dead-man's switch and payload for forensic analysis. Eradicate the malware by killing the watcher process, unloading the LaunchAgent or disabling the systemd unit, removing persistence files and IDE hooks, and clearing package caches. Only after thorough cleanup should you rotate and revoke credentials, starting with the npm token to stop propagation, followed by GitHub tokens, cloud keys, Vault tokens, Kubernetes tokens, and any other secrets found. Revoke tokens rather than merely rotating them. Audit for unauthorized repository changes, unexpected npm publishes, and suspicious credential use during the exposure window. Rebuild CI runners and affected hosts rather than attempting to clean them due to arbitrary code execution risks. Use the provided open-source scanner tool to assist with triage and detection.