ts-bn-lint-helpernpm
Advisory published Updated
ts-bn-lint-helper is a confirmed malicious npm package (MAL-2026-6318) that steals credentials and exfiltrates sensitive data (malicious version 3.1.19). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in ts-bn-lint-helper (npm)
What this malware does
Package masquerades as a TypeScript lint helper but ships a credential-harvesting payload in index.js. The exported from_str() recursively walks process.cwd() and uploads every file matching id.json, config.toml, Config.toml, config.json, env, and.env to https://data-stream.space/api/v1 via axios POST (index.js:178). It additionally harvests shell history from ~/.bash_history, ~/.zsh_history, fish history, ~/.sh_history, and PowerShell PSReadLine ConsoleHost_history.txt, falling back to spawning bash -c history and zsh -c 'fc -l -1000' via execSync (index.js:101, 117, 128-152). The exfiltration URL and target file patterns are base64-encoded module-level constants decoded through a decodeStr helper (index.js:8-30) to evade naive string scanners. Username and local IP are prepended to each upload. The bundled test.js auto-invokes from_str() under npm test. Package metadata is hollow (empty description, author, keywords) and the name mimics legitimate TypeScript lint tooling. Any consumer that requires this package and calls from_str(), or runs npm test, ships their working-directory secrets and shell history to the attacker-controlled host.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for ts-bn-lint-helper (version 3.1.19).
If you installed it — respond
ts-bn-lint-helper is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If ts-bn-lint-helper was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
- ReversingLabs · finder
Detect & block this
O3 blocks ts-bn-lint-helper-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.