{"id":"MAL-2026-12628","summary":"Malicious code in claims-microgen-templates (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (9d4eefb6f5d91cfe86acf925e0d84b5cb34336f98cf73586e01d17418d02454f)\nOn require of the package, index.js loads _compat.js which fetches a platform-specific binary from string-concatenated Cloudflare Workers hosts (oob-worker.cf1-01-adf.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev) with a DNS-TXT chunked fallback via sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru. Destination hostnames are reassembled from split string arrays via.join() to evade static string scans, with decoy 'telemetry'/'analytics' comments. The fetched payload is written to a randomized dotfile under /var/tmp (or dotnet_diag_*.exe under %TEMP% on Windows), chmodded 0755, and spawned detached via /bin/sh or cmd. Execution is gated by a /tmp/.analytics_state freshness marker. No hash/signature verification, no publisher-matching host, and no relation to the package's stated 'templates' purpose.\n","modified":"2026-08-05T14:35:56.935594828Z","published":"2026-08-05T14:03:45Z","database_specific":{"malicious-packages-origins":[{"versions":["35.7.1"],"id":"IN-MAL-2026-015148","import_time":"2026-08-05T14:20:07.057620425Z","modified_time":"2026-08-05T14:03:45Z","sha256":"9d4eefb6f5d91cfe86acf925e0d84b5cb34336f98cf73586e01d17418d02454f","source":"amazon-inspector"}]},"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/claims-microgen-templates/v/35.7.1"}],"affected":[{"package":{"name":"claims-microgen-templates","ecosystem":"npm","purl":"pkg:npm/claims-microgen-templates"},"versions":["35.7.1"],"database_specific":{"cwes":[{"name":"Embedded Malicious Code","cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature."}],"indicators":{"package_integrity":[{"hashes":{"sha1":"73682b298640cfe0d75e4ffc0194aa0ad94b1de7","sha512_sri":"sha512-56h/TuoaZZjTsjckK0NoJE8naHph60+2APeQ4JQFSXxwTKWoZsXdRARQibpq7aJv0PN8EI1e2TWWisoYvv97XQ=="},"filename":"claims-microgen-templates-35.7.1.tgz"}],"evidence_files":[{"sha256":"ea3ac074a628b0d360b001d4d2bd9331c08762b8d3346b15bb5f85ea4e9fc12f","tlsh":"94a1846a16a670194bb0d7e4c6175416f65af66373808294f79ca5c81fb222483b2efc","path":"_compat.js"}]},"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/claims-microgen-templates/MAL-2026-12628.json"}}],"schema_version":"1.8.0","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}