{"id":"PYSEC-2026-1075","aliases":["MAL-2026-5326"],"title":"Malicious code in tiktoken-mcp (PyPI)","summary":"Malicious code in tiktoken-mcp (PyPI)","severity":"none","vendor":"tiktoken-mcp","product":"tiktoken-mcp","ecosystem":"pip","affected":["tiktoken-mcp"],"published":"2026-07-07","updated":"2026-07-07","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/PYSEC-2026-1075","references":[{"url":"https://inspector.pypi.io/project/tiktoken-mcp/0.13.2/packages/5c/58/895febe9c7cc34d3e4d64699ec40ac0b378392db3cfda3c93b7af27da95d/tiktoken_mcp-0.13.2-py3-none-any.whl/tiktoken-setup.pth"},{"url":"https://www.endorlabs.com/learn/shai-hulud-hades-wave-hits-six-pypi-bioinformatics-packages"},{"url":"https://www.stepsecurity.io/blog/the-hades-campaign-pypi-packages"}],"tags":["osv","pip"],"ingestedAt":"2026-07-08T18:34:40.004Z","slug":"PYSEC-2026-1075","body":"## Overview\n\nPart of the \"Hades\" wave of the Shai-Hulud supply-chain campaign. On 2026-06-08,\nmalicious phantom releases of tiktoken-mcp were published to PyPI using stolen\ncredentials. The package executes a bundled JavaScript payload (via the Bun\nruntime) on import that harvests and exfiltrates credentials and attempts\nself-propagation. This entry is a summary; behavior may not be fully\ncharacterized here. See the linked references for detailed analysis and\nindicators of compromise.\n\n\n## Affected packages\n\n- `tiktoken-mcp`\n\n## Remediation\n\nRefer to the advisory for the patched release.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}