| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| ImpactThe attacker can validate if a user exists by checking the time login returns. This timing difference can be used to enumerate valid usernames, after which an attacker could attempt brute force attacks.
PatchesThis vulnerability has been patched, implementing a timing-safe form login authenticator that ensures consistent response times regardless of whether a user exists or not.
Technical DetailsThe vulnerability was caused by different response times when:
* A valid username was provided (password hashing occurred)
* An invalid username was provided (no password hashing occurred)
The fix introduces a TimingSafeFormLoginAuthenticator that performs a dummy password hash verification even for non-existent users, ensuring consistent timing.
WorkaroundsNo workarounds are available. Users should upgrade to the patched version.
References * https://owasp.org/www-project-web-security-testing-guide/latest/4-Web_Application_Security_Testing/03-Identity_Management_Testing/04-Testing_for_Account_Enumeration_and_Guessable_User_Account |
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| Failed login response could be different depending on whether the username was local or central. |
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| A vulnerability has been identified in Mendix Runtime V10 (All versions < V10.17.0 only if the basic authentication mechanism is used by the application), Mendix Runtime V10.12 (All versions < V10.12.11 only if the basic authentication mechanism is used by the application), Mendix Runtime V10.6 (All versions < V10.6.19 only if the basic authentication mechanism is used by the application), Mendix Runtime V8 (All versions < V8.18.33 only if the basic authentication mechanism is used by the application), Mendix Runtime V9 (All versions < V9.24.31 only if the basic authentication mechanism is used by the application). The authentication mechanism of affected applications contains an observable response discrepancy vulnerability when validating usernames. This could allow unauthenticated remote attackers to distinguish between valid and invalid usernames. |
| User names used to access the web management interface are limited to
the device identifier, which is a numerical identifier no more than 10
digits. A malicious actor can enumerate potential targets by
incrementing or decrementing from known identifiers or through
enumerating random digit sequences. |
| Cosmos provides users the ability self-host a home server by acting as a secure gateway to your application, as well as a server manager. By monitoring the error code returned in the login, it is possible to figure out whether a user exist or not in the database. Patched in 0.17.7. |
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| Fastapi OPA is an opensource fastapi middleware which includes auth flow. HTTP `OPTIONS` requests are always allowed by `OpaMiddleware`, even when they lack authentication, and are passed through directly to the application. `OpaMiddleware` allows all HTTP `OPTIONS` requests without evaluating it against any policy. If an application provides different responses to HTTP `OPTIONS` requests based on an entity existing (such as to indicate whether an entity is writable on a system level), an unauthenticated attacker could discover which entities exist within an application. This issue has been addressed in release version 2.0.1. All users are advised to upgrade. There are no known workarounds for this vulnerability. |
| A vulnerability in SAP Financial Service Claims Management RFC function ICL_USER_GET_NAME_AND_ADDRESS allows user enumeration and potential disclosure of personal data through response discrepancies, causing low impact on confidentiality with no impact on integrity or availability. |
| Kaiten 57.128.8 allows remote attackers to enumerate user accounts via a crafted POST request, because a login response contains a user_email field only if the user account exists. |
| A vulnerability has been identified in Mendix Runtime V10 (All versions < V10.21.0), Mendix Runtime V10.12 (All versions < V10.12.16), Mendix Runtime V10.18 (All versions < V10.18.5), Mendix Runtime V10.6 (All versions < V10.6.22), Mendix Runtime V8 (All versions < V8.18.35), Mendix Runtime V9 (All versions < V9.24.34). Affected applications allow for entity enumeration due to distinguishable responses in certain client actions. This could allow an unauthenticated remote attacker to list all valid entities and attribute names of a Mendix Runtime-based application. |
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| The login mechanism of Sage DPW 2025_06_004 displays distinct responses for valid and invalid usernames, allowing enumeration of existing accounts in versions before 2021_06_000. On-premise administrators can toggle this behaviour in newer versions. |
| User enumeration in ESET Protect (on-prem) via Response Timing. |
| Raytha CMS is vulnerable to User Enumeration in password reset functionality. Difference in messages could allow an attacker to determine if the login is valid or not, enabling a brute force attack with valid logins.
This issue was fixed in version 1.5.0. |
| Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.51 and 9.6.0-alpha.40, the Pages route and legacy PublicAPI route for resending email verification links return distinguishable responses depending on whether the provided username exists and has an unverified email. This allows an unauthenticated attacker to enumerate valid usernames by observing different redirect targets. The existing emailVerifySuccessOnInvalidEmail configuration option, which is enabled by default and protects the API route against this, did not apply to these routes. This issue has been patched in versions 8.6.51 and 9.6.0-alpha.40. |
| WWBN AVideo is an open source video platform. In versions up to and including 26.0, the password recovery endpoint at `objects/userRecoverPass.php` performs user existence and account status checks before validating the captcha. This allows an unauthenticated attacker to enumerate valid usernames and determine whether accounts are active, inactive, or banned — at scale and without solving any captcha — by observing three distinct JSON error responses. Commit e42f54123b460fd1b2ee01f2ce3d4a386e88d157 contains a patch. |
