{"id":"MAL-2026-18447","kind":"package","aliases":["MAL-2026-18447"],"related":[],"title":"Malicious code in zystcdemo (npm)","description":"zystcdemo presents itself as a simple date formatting utility and runs its postinstall payload on npm install with `node postinstall.js`. The payload collects the `whoami` result, hostname, platform, and current time, then sends them in a POST request to `https://srctest.zystcc.cn/collect`; npm account `zyst` published it on 2026-10-29 (UTC).","summary":null,"severity":"critical","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[{"name":"zystcdemo","fixed":[],"affected":"= 1.0.0","ecosystem":"npm"}],"ecosystems":["npm"],"tags":["malicious","package"],"not_affected_if":[],"how_to_check":null,"fix":null,"status":"open","published_at":"2026-10-29T07:22:48+00:00","first_seen_at":"2026-11-02T06:21:27+00:00","triaged_at":"2026-11-02T06:21:45+00:00","updated_at":"2026-11-02T06:23:10+00:00","category":"package","confidence":null,"triage":null,"analyst_status":null,"analyst_note":null,"search":"'-10':64C '-18447':8A,11A '-2026':7A,10A '-29':65C '/collect':56C '2026':63C 'account':58C 'code':2A 'collect':37C 'current':44C 'date':21C 'format':22C 'hostnam':41C 'instal':31C 'mal':6A,9A 'malici':1A,13B 'node':33C 'npm':5A,30C,57C 'packag':14B 'payload':28C,36C 'platform':42C 'post':51C 'postinstal':27C 'postinstall.js':34C 'present':16C 'publish':60C 'request':52C 'result':40C 'run':25C 'send':47C 'simpl':20C 'srctest.zystcc.cn':55C 'srctest.zystcc.cn/collect':54C 'time':45C 'utc':66C 'util':23C 'whoami':39C 'zyst':59C 'zystcdemo':4A,12A,15C","nicknames":[],"mitigations":[],"who_affected":null,"tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":null,"audience":null,"plain_action":null,"pkeys":["zystcdemo"],"ptokens":["zystcdemo"],"labels":["critical","malicious","npm","package"],"first_public_at":"2026-10-29T07:22:48+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"osv-malicious","external_id":"MAL-2026-18447","url":"https://osv.dev/vulnerability/MAL-2026-18447","severity":"critical","published_at":"2026-10-29T07:22:48+00:00","modified_at":"2026-11-02T05:15:06+00:00","first_seen_at":"2026-11-02T06:21:27+00:00","fetched_at":"2026-11-02T06:21:27+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}