CVE-2025-50538
Published: 06 October 2025
Summary
CVE-2025-50538 is a high-severity Cross-site Scripting (CWE-79) vulnerability in Flowiseai Flowise. Its CVSS base score is 8.2 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 28.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
This vulnerability is AI-related — categorised as AI Agent Protocols and Integrations; in the Other ATLAS/OWASP Terms risk domain.
The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-15 (Information Output Filtering).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Validates and sanitizes inputs to chat logs, preventing injection of malicious IFRAME elements that enable XSS when viewed by admins.
Filters or encodes chat log outputs to neutralize XSS payloads like malicious IFRAMEs before rendering for admin viewing.
Requires timely flaw remediation, such as upgrading Flowise to 3.0.5 or later, to address the specific XSS vulnerability in chat log handling.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Stored XSS vulnerability in FlowiseAI enables exploitation of a public-facing web application (T1190) for arbitrary JavaScript execution (T1059.007) in an admin's browser, facilitating browser session hijacking through theft of credentials from localStorage (T1185).
NVD Description
Flowise before 3.0.5 allows XSS via an IFRAME element when an admin views the chat log.
Deeper analysisAI
CVE-2025-50538 is a cross-site scripting (XSS) vulnerability affecting Flowise versions before 3.0.5. The flaw enables the injection of a malicious IFRAME element that executes when an administrator views the chat log. It carries a CVSS v3.1 base score of 8.2 (AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N) and maps to CWE-79.
An unauthenticated attacker with network access can exploit this vulnerability by tricking an administrator into viewing a crafted chat log containing the malicious IFRAME, which requires user interaction. Successful exploitation results in high confidentiality impact, such as potential theft of sensitive data like admin session tokens, low integrity impact, and no availability impact, with a changed scope that may affect additional resources.
The official Flowise security advisory (GHSA-964p-j4gg-mhwc), pull request #4905, and release notes for version 3.0.5 confirm that the issue is fixed in Flowise 3.0.5. Mitigation involves upgrading to version 3.0.5 or later.
Details
- CWE(s)
Affected Products
AI Security AnalysisAI
- AI Category
- AI Agent Protocols and Integrations
- Risk Domain
- Other ATLAS/OWASP Terms
- OWASP Top 10 for LLMs 2025
- None mapped
- Classification Reason
- FlowiseAI is an open-source low-code platform for building customized LLM flows and AI agents using LangChainJS, fitting the 'Other Platforms' category as a UI/tooling platform for AI application development.