Vulnerability · Published Aug 6, 2026 · Assigned by WSO2
CVE-2025-13736Username Enumeration via Login Interface in Multiple WSO2 Products Allows User Account Discovery
Low 3.7
In plain English
A low-severity security flaw in WSO2 API Manager from WSO2. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities).
Official description
When Multi-Attribute Login is enabled, the login interface fails to consistently mask the existence of user accounts. For valid users, the server resolves and displays their canonical username, while for non-existent users, it echoes the original input. This occurs regardless of the validate_username configuration. The discovery of valid usernames can increase the risk of brute force attacks, social engineering attacks, and targeted information leakage. Attackers can leverage this information to craft more effective phishing campaigns or social engineering tactics to compromise user accounts or extract sensitive data.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| WSO2 | WSO2 Identity Server as Key Manager | 5.10.0 – before 5.10.0.371 |
| WSO2 | WSO2 Identity Server | 5.10.0 – before 5.10.0.3805.11.0 – before 5.11.0.4276.0.0 – before 6.0.0.2546.1.0 – before 6.1.0.2557.0.0 – before 7.0.0.1327.1.0 – before 7.1.0.407.2.0 – before 7.2.0.2 |
| WSO2 | WSO2 Open Banking AM | 2.0.0 – before 2.0.0.400 |
| WSO2 | WSO2 API Manager | 3.1.0 – before 3.1.0.3513.2.0 – before 3.2.0.4554.0.0 – before 4.0.0.375 |
| WSO2 | WSO2 Open Banking IAM | 2.0.0 – before 2.0.0.420 |
Weakness: CWE-203 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N