@bytemend/mfebus

{"schema_version":"1.7.4","id":"MAL-2026-6213","published":"2026-06-19T15:13:09Z","modified":"2026-08-13T22:13:34.337517827Z","aliases":["GHSA-hfjj-fph3-hp6h"],"summary":"Malicious code in @bytemend/mfebus (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (b3d53776853d18aabf967b0f1882eb45f2164feedd600eeccc927f496002f5e4)\nThe package advertises itself as a small in-memory pubsub library but its main entry `dist/index.js` eagerly `require()`s `dist/bootstrap.js`, a 277KB obfuscator.io-protected blob (string-array rotation, control-flow flattening, RC4 string decoder, self-defending wrappers) whose decoded behavior is a remote-code dropper. On require — and automatically when the module is loaded inside a forked Node child via `maybeInstallAutoIpc()`/`addIpcTarget(process)` — the bootstrap: (1) re-spawns `process.execPath` detached with the original argv and an env-var sentinel as an anti-analysis re-entry guard (`child_process.spawn(process.execPath, process.argv.slice(1), { detached:true, windowsHide:true, stdio:'ignore' })` followed by `unref()`); (2) opens an HTTPS request to a destination resolved from RC4-decrypted strings, follows redirects, and writes the response under `os.homedir()/.cache/<dir>/`; (3) verifies a SHA-256 against a sidecar metadata file and then `require()`s the downloaded payload, executing attacker-controlled code in the installer's Node process. Before doing any of this, it installs no-op handlers for `uncaughtException`, `unhandledRejection`, and `warning` and wraps the flow in try/catch with `process.exit(0)` paths so failures are silently swallowed and never reach host application logs or telemetry. None of this network, child-process, or self-respawn behavior is disclosed in the README, and none of it is consistent with the package's stated pubsub purpose. Any project that imports this package — directly, transitively, or in a forked worker — fetches and executes attacker-controlled code on the installer's machine.\n\n## Source: ghsa-malware (ad9196d4fa856a26a59f6fb1d489fae7fc76f74a6a09783873307289d6029248)\nAny computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.\n","affected":[{"package":{"name":"@bytemend/mfebus","ecosystem":"npm"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"}]}],"versions":["1.4.3","1.4.4","1.4.1","1.4.5","1.4.0","1.4.2"],"database_specific":{"cwes":[{"cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code"},{"cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code"},{"cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code"},{"cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code"},{"cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code"},{"cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code"},{"cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code"}],"indicators":{"evidence_files":[{"path":"dist/bootstrap.js","sha256":"a9a28f2e9f7e0348092682940b3bf63d47a63afc18eb8bfe628e5ddab0d73b47","tlsh":"a6449730b3c07c9425479f7b332ef5e5f92e5fa934a8088bd065bc64a6ea915dad0730"}],"package_integrity":[{"filename":"mfebus-1.4.3.tgz","hashes":{"sha1":"35d1f3ede98964880c4759a2346ab1f1893c130b","sha512_sri":"sha512-kxFo8/qHEMUTvwCNgrwOB6TyO1Nr3gcggKfk95jqUR5pz8ITygFiCQ3dKYVDs7jJUmgHbtvPCVwfYXvXRlJRkA=="}}]}}}],"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/@bytemend/mfebus/v/1.4.3"},{"type":"PACKAGE","url":"https://www.npmjs.com/package/@bytemend/mfebus/v/1.4.4"},{"type":"PACKAGE","url":"https://www.npmjs.com/package/@bytemend/mfebus/v/1.4.1"},{"type":"PACKAGE","url":"https://www.npmjs.com/package/@bytemend/mfebus/v/1.4.5"},{"type":"PACKAGE","url":"https://www.npmjs.com/package/@bytemend/mfebus/v/1.4.0"},{"type":"PACKAGE","url":"https://www.npmjs.com/package/@bytemend/mfebus/v/1.4.2"},{"type":"ADVISORY","url":"https://github.com/advisories/GHSA-hfjj-fph3-hp6h"}],"database_specific":{"malicious-packages-origins":[{"id":"IN-MAL-2026-007079","import_time":"2026-06-19T15:41:55.709372876Z","modified_time":"2026-06-19T15:13:09Z","sha256":"b3d53776853d18aabf967b0f1882eb45f2164feedd600eeccc927f496002f5e4","source":"amazon-inspector","versions":["1.4.3"]},{"id":"IN-MAL-2026-007299","import_time":"2026-06-23T16:54:15.987139357Z","modified_time":"2026-06-23T16:22:44Z","sha256":"95a912477c1c7fa0328dccbde3db7950abb96de370a6ee8114437d1b9aeba859","source":"amazon-inspector","versions":["1.4.4"]},{"id":"IN-MAL-2026-007303","import_time":"2026-06-23T16:54:16.356715105Z","modified_time":"2026-06-23T16:22:47Z","sha256":"acfe33e234ed9e63bccf613d5e6d3243411615bcb01277c1a1e84a32a890761a","source":"amazon-inspector","versions":["1.4.1"]},{"id":"IN-MAL-2026-007300","import_time":"2026-06-23T16:54:16.060033562Z","modified_time":"2026-06-23T16:22:45Z","sha256":"b864cc81e98f559bc4778dcd4ed9ba0f47b06f6b6c2ff80fd40001f5f224aadf","source":"amazon-inspector","versions":["1.4.5"]},{"id":"IN-MAL-2026-007301","import_time":"2026-06-23T16:54:16.102691053Z","modified_time":"2026-06-23T16:22:46Z","sha256":"b9845642168995233a690f89f2f24e2fccf2c72f1901c21e63e267201de61254","source":"amazon-inspector","versions":["1.4.0"]},{"id":"IN-MAL-2026-007302","import_time":"2026-06-23T16:54:16.249291954Z","modified_time":"2026-06-23T16:22:46Z","sha256":"dc0a4508c0ac487d8b97e0e81fe032bbf60ab5111452b07cae341d810d1461d9","source":"amazon-inspector","versions":["1.4.2"]},{"id":"GHSA-hfjj-fph3-hp6h","import_time":"2026-08-13T22:11:44.621516131Z","modified_time":"2026-08-13T15:07:49Z","ranges":[{"events":[{"introduced":"0"}],"type":"SEMVER"}],"sha256":"ad9196d4fa856a26a59f6fb1d489fae7fc76f74a6a09783873307289d6029248","source":"ghsa-malware"}]},"credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}