@mexc/shared-utilsnpm
Advisory published Updated
@mexc/shared-utils is a confirmed malicious npm package (MAL-2026-14049) that steals credentials and exfiltrates sensitive data (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @mexc/shared-utils (npm)
What this malware does
Package published to the public npm registry under the @mexc scope without evidence of scope ownership. package.json declares a postinstall hook ("postinstall": "node postinstall.js") that runs on any installer whose resolver falls back to the public registry when resolving @mexc/shared-utils. The postinstall script collects host metadata — os.hostname(), os.userInfo().username, process.getuid(), process.cwd(), platform, node version, and multiple npm_* environment variables (npm_config_registry, npm_config_user_agent, npm_execpath, INIT_CWD) — and writes the data to os.tmpdir()/mexc-poc-execution-proof.json. The current shipped script performs local write only with no outbound network call, but the install-time code-execution primitive against any CI/build system that resolves the @mexc scope publicly is the classic dependency-confusion pattern; the author controls the code that runs and can change the payload in any future version.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for @mexc/shared-utils (version 1.0.0).
If you installed it — respond
@mexc/shared-utils 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 @mexc/shared-utils 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
Detect & block this
O3 blocks @mexc/shared-utils-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.