PT-2026-53628 · Pypi · Upsonic

Published 2026-06-29 · Updated 2026-06-29

OSV

CVSS v3.1

9.8

Critical

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Upsonic 0.71.6 contains a remote code execution vulnerability in its MCP server/task creation functionality. The application allows users to define MCP tasks with arbitrary command and args values. Although an allowlist exists, certain allowed commands (npm, npx) accept argument flags that enable execution of arbitrary OS commands. Maliciously crafted MCP tasks may lead to remote code execution with the privileges of the Upsonic process. In version 0.72.0 Upsonic added a warning about using Stdio servers being able to execute commands directly on the machine.

Fix

Related Identifiers

PYSEC-2026-559

Affected Products

Upsonic

References · 7

• https://nvd.nist.gov/vuln/detail/CVE-2026-30625 · Security Note
• https://osv.dev/vulnerability/PYSEC-2026-559 · Vendor Advisory
• https://github.com/Upsonic/Upsonic/commit/855053fce0662227d9246268ff4a0844b481a305 · Note
• https://github.com/Upsonic/Upsonic · Note
• https://pypi.org/project/upsonic · Note
• https://ox.security/blog/mcp-supply-chain-advisory-rce-vulnerabilities-across-the-ai-ecosystem · Note
• https://github.com/advisories/GHSA-cw73-5f7h-m4gv · Note