Flowise before 3.1.2 sets Access-Control-Allow-Origin to a hardcoded wildcard (*) on its text-to-speech (TTS) generation endpoint (packages/server/src/controllers/text-to-speech/index.ts), independent of the server's configured CORS policy. This bypasses the server's otherwise restrictive default CORS configuration (getCorsOptions()) and allows any webpage to make cross-origin requests that trigger TTS generation using stored credentials, enabling drive-by cross-origin credential abuse.
Flowise before 3.1.0 (affected versions 3.0.13 and earlier) uses a weak hardcoded default secret ('flowise') for the express-session middleware when the EXPRESS_SESSION_SECRET environment variable is not set (packages/server/src/enterprise/middleware/passport/index.ts). Because this default secret is publicly visible in the source code, an attacker can forge valid signed session cookies to impersonate any user and bypass authentication.
Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.
Flowise through 2.2.4 contains an unauthenticated arbitrary file upload vulnerability in the /api/v1/attachments endpoint when storageType is set to local. Attackers can exploit path traversal in the chatId and chatflowId parameters to upload malicious files to arbitrary directories, potentially enabling remote code execution and server compromise.
Flowise before 3.0.6 (affected versions 2.2.8 and earlier) contains an arbitrary file access vulnerability due to missing validation that the chatflowId and chatId parameters are UUIDs or numbers in file handling operations. By supplying a path-traversal value (e.g., '../../../../../tmp') as the chatflow id, an unauthenticated attacker can use the /api/v1/chatflows endpoint (via addBase64FilesToStorage) to write arbitrary files, and the /api/v1/get-upload-file and /api/v1/openai-assistants-file/download endpoints (via streamStorageFile) to read arbitrary files. Arbitrary file write may lead to remote code execution.
Flowise before 3.0.10 (affected versions 3.0.7 and earlier) fails to invalidate existing sessions and session tokens after a user changes their password. An attacker who already holds an active session, for example via a stolen session token or a device left logged in, remains authenticated as the legitimate user even after the user rotates their credentials, undermining the security purpose of the password change.
Flowise before 3.0.6 (affected versions 2.2.7-patch.1 and earlier) contains an unsandboxed remote code execution vulnerability in the Custom MCP feature, which is designed to execute OS commands such as launching local MCP servers. Because Flowise's authentication and authorization model is minimal and lacks role-based access control, and the default installation runs without authentication unless FLOWISE_USERNAME and FLOWISE_PASSWORD are set, an attacker can send a crafted JSON payload with the header 'x-request-from: internal' to the /api/v1/node-load-method/customMCP endpoint to execute arbitrary OS commands, resulting in complete compromise of the platform container or server.
Flowise contains a path traversal vulnerability in the /api/v1/document-store/loader/process endpoint that allows unauthenticated attackers to write arbitrary files to the filesystem. Attackers can exploit unsanitized fileName parameters with ../ sequences to overwrite critical files like package.json and achieve remote code execution when the application restarts.
Flowise before 3.0.6 contains an arbitrary file read vulnerability in the chatId parameter of the /api/v1/get-upload-file and /api/v1/openai-assistants-file/download endpoints. The chatId value is not validated and is passed to streamStorageFile(), where a fallback file-lookup path constructed without the orgId is evaluated after the storage-directory containment check, allowing path traversal beyond the intended storage directory. Unauthenticated attackers can read sensitive files such as /root/.flowise/database.sqlite, exposing all database content in the default configuration.
Flowise contains an authentication bypass vulnerability in the unprotected /api/v1/account/register endpoint that allows unauthenticated attackers to create user accounts. Remote attackers can exploit this endpoint to register arbitrary accounts and authenticate to the system, gaining full API access without credentials.