{"id":"MAL-2026-5189","summary":"Malicious code in arjson (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (00290c05e0c41a8f51d38c629ade5b3fe76f2a89302db8daac669b0c80d13197)\npackage.json declares `\"preinstall\": \"./.github/scripts/precheck\"`, which on `npm install` executes a 976KB UPX-packed Linux ELF binary shipped under `.github/scripts/` (a path designed to look like CI tooling). The binary has no accompanying source, is compressed with UPX (`http://upx.sf.net` banner present in the packed image) to defeat static inspection, and its embedded strings reveal capabilities far beyond anything a JSON serialization library would require: libbpf/eBPF (`LIBBPF_0.0`), kernel tracing (`PTRACE`), netlink socket-diag enumeration (`NETLINK_*_DIAG`, `INODE`), HTTP client primitives (`HTTP/1.1`, `POST`, `DELETE`), GitHub API client (`2022-11-28`), Windows path handling (`USERPROFILE`), and asymmetric crypto (Ed25519, MLKEM, RSA_PKCS1_). Any developer or CI system running `npm install arjson` on Linux will execute opaque packed native code with kernel-level introspection and HTTP-exfiltration capability. The package is advertised as a JSON library; no legitimate purpose exists for shipping a packed eBPF/HTTP-capable preinstall binary.\n\n## Source: google-open-source-security (146faaf0d97c6a533a969bc3f3f117811f9317dc865ed4ab37f1679842ddeaae)\nThis package was compromised as part of the IronWorm campaign. This campaign executes a malicious binary payload during installation via a preinstall hook. The payload is a Rust-built infostealer that targets developer environments, scanning for and harvesting credentials related to cloud providers, object storage, databases, source-control, package registries, and AI developer tools. It also targets cryptocurrency wallets, specifically injecting a malicious JavaScript hook into the Exodus desktop wallet to capture passwords and recovery phrases. Furthermore, the malware exhibits worm-like behavior by stealing GitHub and NPM credentials to push malicious updates to the victim's repositories and publish trojanized packages, and it uses an eBPF-based kernel rootkit to hide its processes and network connections on Linux systems.\n","modified":"2026-06-12T20:01:47.019483903Z","published":"2026-06-04T22:27:40Z","database_specific":{"malicious-packages-origins":[{"modified_time":"2026-06-04T22:28:51.769005667Z","versions":["0.1.4"],"source":"google-open-source-security","sha256":"146faaf0d97c6a533a969bc3f3f117811f9317dc865ed4ab37f1679842ddeaae","import_time":"2026-06-04T22:42:01.227855Z"},{"versions":["0.1.4"],"source":"amazon-inspector","sha256":"00290c05e0c41a8f51d38c629ade5b3fe76f2a89302db8daac669b0c80d13197","import_time":"2026-06-12T19:44:11.095315849Z","id":"IN-MAL-2026-006127","modified_time":"2026-06-12T19:09:35Z"}]},"references":[{"type":"ARTICLE","url":"http://www.ox.security/blog/ironworm-supply-chain-malware-hits-npm/"},{"type":"ARTICLE","url":"https://research.jfrog.com/post/iron-worm-shai-hulud-rustier-cousin/"},{"type":"PACKAGE","url":"https://www.npmjs.com/package/arjson/v/0.1.4"}],"affected":[{"package":{"name":"arjson","ecosystem":"npm","purl":"pkg:npm/arjson"},"versions":["0.1.4"],"database_specific":{"indicators":{"evidence_files":[{"path":".github/scripts/precheck","sha256":"36abd242ddaa27f0160c539377a0e92cf781c1695137850acc87e3892b436d36","tlsh":"0c2533ab0025062b904d957a58963bd279c17c81afcc3662664dae742fb59c3cf63fc3"}],"package_integrity":[{"hashes":{"sha1":"3a327976602c78a813813713716657dd26b00a82","sha512_sri":"sha512-+m6kNJ+Y5Fe1w7YiVJcXByTSBcFsz/Fil5E73+FdSGFkf6z09EXHK0Cyykf7uUfYTe3PL3UzHBGlKdCpP4LnEg=="},"filename":"arjson-0.1.4.tgz"}]},"cwes":[{"name":"Embedded Malicious Code","cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature."}],"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/arjson/MAL-2026-5189.json"}}],"schema_version":"1.7.5","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}