CVE-2025-55346
published 2025-08-14CVE-2025-55346: User-controlled input flows to an unsafe implementation of a dynamic Function constructor, allowing network attackers to run arbitrary unsandboxed JS code in…
PriorityP187critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
ITWVulnCheck KEV
Exploited in the wild
EPSS
17.42%
96.7th percentile
User-controlled input flows to an unsafe implementation of a dynamic Function constructor, allowing network attackers to run arbitrary unsandboxed JS code in the context of the host, by sending a simple POST request.
Affected
1 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| flowiseai | flowise | 0 – 2.2.7-patch.1 | — |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vulncheck9.8CRITICAL
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OSV
Flowise vulnerable to RCE via Dynamic function constructor injection
osv·2025-10-06
CVE-2025-55346 [CRITICAL] Flowise vulnerable to RCE via Dynamic function constructor injection
Flowise vulnerable to RCE via Dynamic function constructor injection
### Summary
User-controlled input flows to an unsafe implementaion of a dynamic Function constructor , allowing a malicious actor to run JS code in the context of the host (not sandboxed) leading to RCE.
### Details
When creating a new `Custom MCP` Chatflow in the platform, the MCP Server Config displays a placeholder hinting at an example of the expected input structure:
```json
{
"command": "npx",
"args": ["-y", "@modelcontextprotocol/server-filesystem", "/path/to/allowed/files"]
}
```
Behind the scene, a `POST` request to `/api/v1/node-load-method/customMCP` is sent with the provided MCP Server Config, with additional parameters (excluded for brevity):
```json
{
...SNIP...
"inputs":{
"mcpServerConfig":{
"command":"
GHSA
Flowise vulnerable to RCE via Dynamic function constructor injection
ghsa·2025-10-06
CVE-2025-55346 [CRITICAL] CWE-627 Flowise vulnerable to RCE via Dynamic function constructor injection
Flowise vulnerable to RCE via Dynamic function constructor injection
### Summary
User-controlled input flows to an unsafe implementaion of a dynamic Function constructor , allowing a malicious actor to run JS code in the context of the host (not sandboxed) leading to RCE.
### Details
When creating a new `Custom MCP` Chatflow in the platform, the MCP Server Config displays a placeholder hinting at an example of the expected input structure:
```json
{
"command": "npx",
"args": ["-y", "@modelcontextprotocol/server-filesystem", "/path/to/allowed/files"]
}
```
Behind the scene, a `POST` request to `/api/v1/node-load-method/customMCP` is sent with the provided MCP Server Config, with additional parameters (excluded for brevity):
```json
{
...SNIP...
"inputs":{
"mcpServerConfig":{
"command":"
VulnCheck
FlowiseAI Flowise Improper Control of Generation of Code ('Code Injection')
vulncheck·2025·CVSS 9.8
CVE-2025-55346 [CRITICAL] FlowiseAI Flowise Improper Control of Generation of Code ('Code Injection')
FlowiseAI Flowise Improper Control of Generation of Code ('Code Injection')
User-controlled input flows to an unsafe implementation of a dynamic Function constructor, allowing network attackers to run arbitrary unsandboxed JS code in the context of the host, by sending a simple POST request.
Affected: FlowiseAI Flowise
Required Action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Exploitation References: https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2025-11-19&host_type=src&vulnerability=cve-2025-55346; https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2025-11-21&host_type=src&vulnerability=cve-2025-55346; https://dashboard.shadowserv
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2025-08-14
Published
Exploited in the wild