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pypi

semmver@1.0.0

Vulnerability report · Last retrieved from osv.dev October 20, 2026 at 10:24 PM UTC

Malicious

OSV ID

MAL-2026-18101

Ecosystem

pypi

Summary

The package is a typosquat-style empty stub (semmver/__init__.py contains only __version__ = '1.0.0') whose only functional code is in setup.py. At pip install time, setup.py calls urllib.request.urlretrieve to download an opaque, unpinned binary from https://c2-worker.crawlnet-claim.workers.dev/dl/pyupd, writes it to a temporary path, and launches it via subprocess.Popen with start_new_session=True and stdout/stderr suppressed, detaching it from the installer process. There is no hash or signature verification, no pinning, and the destination host is unrelated to any legitimate utility purpose; the subdomain is self-labeled 'c2-worker'. Installing this package executes attacker-controlled code on the installer's machine.

Source: amazon-inspector (8de323d5976a26f2d9540680d1706a53bcb3ca743409821e83f7a2f1b60e8594)

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