OS Command Injection in Flowise Custom MCP Server
CVE-2026-56274 affects Flowise before 3.1.2 in the Custom MCP Server feature. The vulnerability consists of multiple OS command injection flaws caused by incomplete command-flag validation in the validateCommandFlags logic and a regex bypass in validateArgsForLocalFileAccess. According to the provided content, an attacker can configure a malicious MCP server and bypass intended restrictions because certain dangerous command patterns are not blocked, including examples such as 'docker build' not being denied and 'npx --yes' bypassing checks that only block '-y'. By abusing these validation weaknesses, an attacker can cause arbitrary operating system commands to be executed on the Flowise host.
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Recent activity
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Cross-references every affected SKU, including bundled OEM variants.
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