date-fmt-helper-xz

{"modified":"2026-08-13T17:16:06Z","published":"2026-08-13T17:16:06Z","schema_version":"1.7.4","id":"MAL-2026-13946","summary":"Malicious code in date-fmt-helper-xz (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (b384650ec0fabdd01a7dfc513cccd25156611a04c17ba0c435b950ddb9215777)\ndate-fmt-helper-xz ships a postinstall.js that runs automatically on npm install. The script opens a TCP connection to the hardcoded remote host 8.135.48.40 on port 4444 and pipes /bin/sh stdio over the socket, granting the remote party interactive shell access on the installer's machine. Bash /dev/tcp and python3 pty.spawn fallbacks are included to maximize the chance the shell succeeds across environments. On failure of the shell paths, the script issues an HTTP GET to http://8.135.48.40/shell/failed and /shell/error with the error message, confirming the same host as attacker command-and-control. The package advertises date formatting; the reverse shell is unrelated to any legitimate functionality.\n","affected":[{"package":{"ecosystem":"npm","name":"date-fmt-helper-xz"},"versions":["1.0.4"],"database_specific":{"cwes":[{"cweId":"CWE-506","description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code"}],"indicators":{"evidence_files":[{"path":"postinstall.js","sha256":"6da6821e4a53bdd6c0e40a6f81a0491b98031c5444cf7582b3ec40c08e4718a2","tlsh":"9811ebe905fad07caf7b247866bfa426211342077819eee4b8ce0b03af125680c123a1"}],"package_integrity":[{"filename":"date-fmt-helper-xz-1.0.4.tgz","hashes":{"sha1":"2f8c3568222ea92fd0674adfa7ae423bd697a0ee","sha512_sri":"sha512-qbAw4z/0/RbrULoAD8wkNyOylP50WAzItrcYb15Cc8MVW6DW2Ar7lWFS9vkHZTsujZN2w2s1YOYyaNXqxaKp2w=="}}]}}}],"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/date-fmt-helper-xz/v/1.0.4"}],"credits":[{"name":"Amazon Inspector","type":"FINDER","contact":["inspector-research@amazon.com"]}],"database_specific":{"malicious-packages-origins":[{"id":"IN-MAL-2026-017637","import_time":"2026-08-13T17:24:45.410047058Z","modified_time":"2026-08-13T17:16:06Z","sha256":"b384650ec0fabdd01a7dfc513cccd25156611a04c17ba0c435b950ddb9215777","source":"amazon-inspector","versions":["1.0.4"]}]}}