Umbraco is a free and open source .NET content management system. Prior to versions 10.8.10 and 13.8.1, based on an analysis of the timing of post login API responses, it's possible to determine whether an account exists. The issue is patched in versions 10.8.10 and 13.8.1. No known workarounds are available.

A vulnerability has been identified in Gridscale X Prepay (All versions < V4.2.1). The affected application is vulnerable to user enumeration due to distinguishable responses. This could allow an unauthenticated remote attacker to determine if a user is valid or not, enabling a brute force attack with valid users.

Observable Response Discrepancy vulnerability in Tridium Niagara Framework on Windows, Linux, QNX, Tridium Niagara Enterprise Security on Windows, Linux, QNX allows Cryptanalysis. This issue affects Niagara Framework: before 4.14.2, before 4.15.1, before 4.10.11; Niagara Enterprise Security: before 4.14.2, before 4.15.1, before 4.10.11.Tridium recommends upgrading to Niagara Framework and Enterprise Security versions 4.14.2u2, 4.15.u1, or 4.10u.11.

D-Link Nuclias Connect firmware versions <= 1.3.1.4 contain an observable response discrepancy vulnerability. The application's 'Login' endpoint returns distinct JSON responses depending on whether the supplied username is associated with an existing account. Because the responses differ in the `error.message`string value, an unauthenticated remote attacker can enumerate valid usernames/accounts on the server. NOTE: D-Link states that a fix is under development.

IBM Cognos Controller 10.4.1, 10.4.2, and 11.0.0 could allow a remote user to enumerate usernames due to differentiating error messages on existing usernames. IBM X-Force ID: 199181.

User enumeration vulnerability in Arconte Áurea 1.5.0.0 version. The exploitation of this vulnerability could allow an attacker to obtain a list of registered users in the application, obtaining the necessary information to perform more complex attacks on the platform.

D-Link Nuclias Connect firmware versions <= 1.3.1.4 contain an observable response discrepancy vulnerability. The application's 'Forgot Password' endpoint returns distinct JSON responses depending on whether the supplied email address is associated with an existing account. Because the responses differ in the `data.exist` boolean value, an unauthenticated remote attacker can enumerate valid email addresses/accounts on the server. NOTE: D-Link states that a fix is under development.

IBM CICS TX Advanced 10.1 could disclose sensitive information to a remote attacker due to observable discrepancy in HTTP responses. IBM X-Force ID: 260814.

User enumeration vulnerability in Password Recovery plugin 1.2 version for Roundcube, which could allow a remote attacker to create a test script against the password recovery function to enumerate all users in the database.

Zitadel is open-source identity infrastructure software. ZITADEL administrators can enable a setting called "Ignoring unknown usernames" which helps mitigate attacks that try to guess/enumerate usernames. If enabled, ZITADEL will show the password prompt even if the user doesn't exist and report "Username or Password invalid". While the setting was correctly respected during the login flow, the user's username was normalized leading to a disclosure of the user's existence. This vulnerability is fixed in 2.71.6, 2.70.8, 2.69.9, 2.68.9, 2.67.13, 2.66.16, 2.65.7, 2.64.6, and 2.63.9.

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.

Shopware 6 is an open commerce platform based on Symfony Framework and Vue. Through the store-api it is possible as a attacker to check if a specific e-mail address has an account in the shop. Using the store-api endpoint /store-api/account/recovery-password you get the response, which indicates clearly that there is no account for this customer. In contrast you get a success response if the account was found. This vulnerability is fixed in Shopware 6.6.10.3 or 6.5.8.17. For older versions of 6.4, corresponding security measures are also available via a plugin. For the full range of functions, we recommend updating to the latest Shopware version.

Omnissa Workspace ONE UEM contains an observable response discrepancy vulnerability. A malicious actor may be able to enumerate sensitive information such as tenant ID and user accounts that could facilitate brute-force, password-spraying or credential-stuffing attacks.

Medtronic CareLink Network allows an unauthenticated remote attacker to initiate a request for security questions to an API endpoint that could be used to determine a valid user account. This issue affects CareLink Network: before December 4, 2025.

A CWE-204 "Observable Response Discrepancy" in the login page in Q-Free MaxTime less than or equal to version 2.11.0 allows an unauthenticated remote attacker to enumerate valid usernames via crafted HTTP requests.

IBM Security Verify Access Appliance and Docker 10.0 through 10.0.8 could allow a remote attacker to enumerate usernames due to an observable response discrepancy of disabled accounts.

Piccolo is an ORM and query builder which supports asyncio. In versions 0.120.0 and prior, the implementation of `BaseUser.login` leaks enough information to a malicious user such that they would be able to successfully generate a list of valid users on the platform. As Piccolo on its own does not also enforce strong passwords, these lists of valid accounts are likely to be used in a password spray attack with the outcome being attempted takeover of user accounts on the platform. The impact of this vulnerability is minor as it requires chaining with other attack vectors in order to gain more then simply a list of valid users on the underlying platform. The likelihood of this vulnerability is possible as it requires minimal skills to pull off, especially given the underlying login functionality for Piccolo based sites is open source. This issue has been patched in version 0.121.0.

Silverware Games is a premium social network where people can play games online. Prior to version 1.3.6, the Password Recovery form would throw an error if the specified email was not found in our database. It would only display the "Enter the code" form if the email is associated with a member of the site. Since version 1.3.6, the "Enter the code" form is always returned, showing the message "If the entered email is associated with an account, a code will be sent now". This change prevents potential violators from determining if our site has a user with the specified email.

An issue discovered in Elenos ETG150 FM transmitter v3.12 allows attackers to enumerate user accounts based on server responses when credentials are submitted.

IBM Aspera Faspex 5.0.0 through 5.0.10 could disclose sensitive username information due to an observable response discrepancy.

Tadiran Telecom Aeonix - CWE-204: Observable Response Discrepancy

Observable Response Discrepancy in the SICK ICR890-4 could allow a remote attacker to identify valid usernames for the FTP server from the response given during a failed login attempt.

IBM Security QRadar EDR 3.12 could disclose sensitive information due to an observable login response discrepancy. IBM X-Force ID: 257697.

TN-5900 Series version 3.3 and prior versions is vulnearble to user enumeration vulnerability. The vulnerability may allow a remote attacker to determine whether a user is valid during password recovery through the web login page and enable a brute force attack with valid users.

Teltonika’s Remote Management System versions prior to 4.10.0 contain a function that allows users to claim their devices. This function returns information based on whether the serial number of a device has already been claimed, the MAC address of a device has already been claimed, or whether the attempt to claim a device was successful. An attacker could exploit this to create a list of the serial numbers and MAC addresses of all devices cloud-connected to the Remote Management System.

Avaya IX Workforce Engagement v15.2.7.1195 - User Enumeration - Observable Response Discrepancy

For failed login attempts, the application returns different error messages depending on whether the login failed due to an incorrect password or a non-existing username. This allows an attacker to guess usernames until they find an existing one.

When supplied with a random MAC address, Snap One OvrC cloud servers will return information about the device. The MAC address of devices can be enumerated in an attack and the OvrC cloud will disclose their information.

pimcore/admin-ui-classic-bundle provides a Backend UI for Pimcore. In affected versions an error message discloses existing accounts and leads to user enumeration on the target via "Forgot password" function. No generic error message has been implemented. This issue has been addressed in version 1.7.4 and all users are advised to upgrade. There are no known workarounds for this vulnerability.

A vulnerability has been identified in Mendix Forgot Password (Mendix 7 compatible) (All versions < V3.7.1), Mendix Forgot Password (Mendix 8 compatible) (All versions < V4.1.1), Mendix Forgot Password (Mendix 9 compatible) (All versions < V5.1.1). The affected versions of the module contain an observable response discrepancy issue that could allow an attacker to retrieve sensitive information.

IBM Aspera Orchestrator 4.0.1 could allow a remote attacker to enumerate usernames due to observable response discrepancies. IBM X-Force ID: 248545.