Vulnerability · Published May 11, 2026 · Assigned by WSO2
CVE-2024-0391Username Enumeration via Email OTP Flow in Multiple WSO2 Products Allows User Account Discovery
Medium 5.3
In plain English
A medium-severity security flaw in Email OTP Authenticator from WSO2. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 8% of all known vulnerabilities).
Official description
The check user account lock states feature within the email OTP flow fails to validate user input, allowing an attacker to infer the existence of registered user accounts. The discovery of valid usernames can increase the risk of brute-force and social engineering attacks. Attackers can leverage this information to craft targeted phishing campaigns or other malicious activities aimed at tricking users into divulging sensitive data, potentially damaging the organization's reputation and leading to regulatory non-compliance and financial consequences.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| WSO2 | WSO2 Identity Server | 5.10.0 – before 5.10.0.3795.11.0 – before 5.11.0.4265.11.0 – before 5.11.0.4316.0.0 – before 6.0.0.2536.1.0 – before 6.1.0.2547.0.0 – before 7.0.0.131 |
| WSO2 | WSO2 Open Banking IAM | 2.0.0 – before 2.0.0.318 |
| WSO2 | WSO2 Identity Server as Key Manager | 5.10.0 – before 5.10.0.267 |
| WSO2 | Email OTP Authenticator | 1.0.18 – before 1.0.18.7 |
| WSO2 | WSO2 Carbon Authenticator Library For EmailOTP | 4.1.0 – before 4.1.0.84.1.4 – before 4.1.4.9 |
| WSO2 | WSO2 Carbon Authenticator Library For EmailOTP | 3.0.5 – before 3.0.5.83.0.24 – before 3.0.24.63.0.26 – before 3.0.26.16 |
Weakness: CWE-204 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N