{"id":"MAL-2026-18092","summary":"Malicious code in test-workalendar-internal (PyPI)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (06eccee3c04982c18f9f348949477e1540d3e63eab7ae66f5d851428d0308597)\ntest-workalendar-internal 0.0.3 ships a custom Hatchling build hook that runs during `pip install` (sdist/wheel build). The hook downloads two standalone binaries — ttyd from github.com/tsl0922/ttyd and cloudflared from github.com/cloudflare/cloudflared — to /tmp/ttyd and /tmp/cloudflared, chmods them executable, and spawns ttyd bound to 127.0.0.1:7681 serving an interactive `bash` shell protected only by a generated basic-auth user/password. It then launches `cloudflared tunnel --url http://127.0.0.1:7681`, parses the resulting `*.trycloudflare.com` URL from cloudflared's stdout, and POSTs a JSON payload containing the tunnel URL, username, and password to the hardcoded collector https://webhook.site/f03cbdbe-704b-4932-a0a7-847d749c19b6. The combined effect is a fully automatic install-time remote shell on the installer's host: a remote party receives the public tunnel URL and basic-auth credentials and can interact with bash on the installer's machine. The package's declared purpose (a weekday/calendar helper) is unrelated to web terminals or tunnels.\n\n## Source: kam193 (9f36e976d0fcf254def6da62e0090bfb2dbdf76176ed316655574408c25cb9a0)\nDuring build, the package creates a web-sharable terminal session and exposes it via a Cloudflare tunnel to the attacker.\n\n\n---\n\nCategory: MALICIOUS - The campaign has clearly malicious intent, like infostealers.\n\n\nCampaign: 2026-10-test-workalendar-internal\n\n\nReasons (based on the campaign):\n\n\n - backdoor\n\n\n - The package overrides the install command in setup.py to execute malicious code during installation.\n","modified":"2026-10-20T18:30:11.131291138Z","published":"2026-10-20T13:00:38Z","database_specific":{"malicious-packages-origins":[{"modified_time":"2026-10-20T13:00:38.972558Z","sha256":"9f36e976d0fcf254def6da62e0090bfb2dbdf76176ed316655574408c25cb9a0","source":"kam193","versions":["0.0.1","0.0.2","0.0.3"],"id":"pypi/2026-10-test-workalendar-internal/test-workalendar-internal","import_time":"2026-10-20T13:19:32.321650537Z"},{"sha256":"06eccee3c04982c18f9f348949477e1540d3e63eab7ae66f5d851428d0308597","source":"amazon-inspector","versions":["0.0.3"],"id":"IN-MAL-2026-021529","import_time":"2026-10-20T18:22:19.440033487Z","modified_time":"2026-10-20T18:16:23Z"}]},"references":[{"type":"WEB","url":"https://bad-packages.kam193.eu/pypi/package/test-workalendar-internal"},{"type":"PACKAGE","url":"https://pypi.org/project/test-workalendar-internal/0.0.3/"}],"affected":[{"package":{"name":"test-workalendar-internal","ecosystem":"PyPI","purl":"pkg:pypi/test-workalendar-internal"},"versions":["0.0.1","0.0.2","0.0.3"],"database_specific":{"cwes":[{"description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code","cweId":"CWE-506"}],"indicators":{"package_integrity":[{"hashes":{"blake2b_256":"00f7bb96379d0b2b8c19e8e1a18b7255864b86ff5a7d3b1caaf540f36f70643c","md5":"d457e27a304fba1412eb699ad8df7f80","sha256":"edd6ed63b185e237ab727e4012c2de2d7145a5e03a683ad19a5e160d9172e22f"},"filename":"test_workalendar_internal-0.0.3.tar.gz"}],"evidence_files":[{"path":"hatch_build.py","sha256":"feaad94fe620e0310b2a9b0252dbc3df8867da521ae3ab17c63cb71c6eae2f1d","tlsh":"77510eb1d4151a6282c14532d41a1a7533e2981b8e07bc75ba6fc2251f9e8bf9178a8f"}]},"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/pypi/test-workalendar-internal/MAL-2026-18092.json"}}],"schema_version":"1.9.0","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"},{"name":"Kamil Mańkowski (kam193)","contact":["https://github.com/kam193","https://bad-packages.kam193.eu/"],"type":"REPORTER"}]}