CVE-2026-30821

Published: Mar 07, 2026 Last Modified: Mar 11, 2026
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 8,2
Source: [email protected]
Attack Vector: network
Attack Complexity: high
Privileges Required: none
User Interaction: none
Confidentiality: N/A
Integrity: N/A
Availability: N/A
CRITICAL 9,8
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: high
Integrity: high
Availability: high

Description

AI Translation Available

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to version 3.0.13, the /api/v1/attachments/:chatflowId/:chatId endpoint is listed in WHITELIST_URLS, allowing unauthenticated access to the file upload API. While the server validates uploads based on the MIME types defined in chatbotConfig.fullFileUpload.allowedUploadFileTypes, it implicitly trusts the client-provided Content-Type header (file.mimetype) without verifying the file's actual content (magic bytes) or extension (file.originalname). Consequently, an attacker can bypass this restriction by spoofing the Content-Type as a permitted type (e.g., application/pdf) while uploading malicious scripts or arbitrary files. Once uploaded via addArrayFilesToStorage, these files persist in backend storage (S3, GCS, or local disk). This vulnerability serves as a critical entry point that, when chained with other features like static hosting or file retrieval, can lead to Stored XSS, malicious file hosting, or Remote Code Execution (RCE). This issue has been patched in version 3.0.13.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0012
Percentile
0,3th
Updated

EPSS Score Trend (Last 10 Days)

434

Unrestricted Upload of File with Dangerous Type

Draft
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Integrity Confidentiality Availability
Potential Impacts:
Execute Unauthorized Code Or Commands
Applicable Platforms
Languages: ASP.NET, Not Language-Specific, PHP
Technologies: Web Server
Likelihood of Exploit: Medium
View CWE Details
Application

Flowise by Flowiseai

Product Information
Vendor Flowiseai
Product Flowise
Version Range Affected
To 3.0.13 (exclusive)
cpe:2.3:a:flowiseai:flowise:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
https://github.com/FlowiseAI/Flowise/releases/tag/flowise%4…
https://github.com/FlowiseAI/Flowise/releases/tag/flowise%403.0.13
https://github.com/FlowiseAI/Flowise/security/advisories/GH…
https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-j8g8-j7fc-43v6