Umbraco is an ASP.NET content management system. Umbraco 10 prior to 10.8.4 with access to the native login screen is vulnerable to a possible user enumeration attack. This issue was fixed in version 10.8.5. As a workaround, one may disable the native login screen by exclusively using external logins.
Umbraco is an ASP.NET content management system (CMS). Starting in version 8.0.0 and prior to versions 8.18.10, 10.8.1, and 12.3.4, a brute force exploit can be used to collect valid usernames. Versions 8.18.10, 10.8.1, and 12.3.4 contain a patch for this issue.
Umbraco is a free and open source .NET content management system. Starting in version 14.0.0 and prior to versions 14.3.2 and 15.1.2, it's possible to determine whether an account exists based on an analysis of response codes and timing of Umbraco management API responses. Versions 14.3.2 and 15.1.2 contain a patch. No known workarounds are available.
UmbracoIdentityExtensions is an Umbraco add-on package that enables easy extensibility points for ASP.Net Identity integration. In affected versions client secrets are not required which may expose some endpoints to untrusted actors. Since Umbraco is not a single-page application, the implicit flow is not safe. For traditional MVC applications, it is recommended to use the authorization code flow, which requires the client to authenticate with the authorization server using a client secret. This flow provides better security, as it involves exchanging an authorization code for an access token and/or ID token, rather than directly returning tokens in the URL fragment. This issue has been patched in commit `e792429f9` and a release to Nuget is pending. Users are advised to upgrade when possible.
Umbraco is an ASP.NET CMS. Some endpoints in the Management API can return stack trace information, even when Umbraco is not in debug mode. This vulnerability is fixed in 14.1.2.
Umbraco is an ASP.NET CMS. Failing webhooks logs are available when solution is not in debug mode. Those logs can contain information that is critical. This vulnerability is fixed in 13.1.1.
Umbraco is an ASP.NET content management system (CMS). Starting in version 8.0.0 and prior to versions 8.18.10, 10.8.1, and 12.3.4, a user enumeration attack is possible when SMTP is not set up correctly, but reset password is enabled. Versions 8.18.10, 10.8.1, and 12.3.4 contain a patch for this issue.
Umbraco is an ASP.NET CMS. In versions 13.0.0 through 13.9.2, 15.0.0 through 15.4.1 and 16.0.0 through 16.1.0, the content delivery API can be restricted from public access where an API key must be provided in a header to authorize the request. It's also possible to configure output caching, such that the delivery API outputs will be cached for a period of time, improving performance. There's an issue when these two things are used together, where caching doesn't vary by the header that contains the API key. As such, it's possible for a user without a valid API key to retrieve a response for a given path and query if it has recently been requested and cached by request with a valid key. This is fixed in versions 13.9.3, 15.4.4 and 16.1.1.
Umbraco, a free and open source .NET content management system, has a vulnerability in versions 10.0.0 through 10.8.10 and 13.0.0 through 13.9.1. Via a request to an anonymously authenticated endpoint it's possible to retrieve information about the configured password requirements. The information available is limited but would perhaps give some additional detail useful for someone attempting to brute force derive a user's password. This information was not exposed in Umbraco 7 or 8, nor in 14 or higher versions. The vulnerability is patched in versions 10.8.11 and 13.9.2.
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.
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.
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.
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.
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.
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.
A remote, unauthenticated attacker can enumerate valid users by sending specific requests to the webservice of MB connect line mymbCONNECT24, mbCONNECT24 and Helmholz myREX24 and myREX24.virtual in all versions through v2.11.2.
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.
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.
A vulnerability in the web-based management interface of Cisco ECE could allow an unauthenticated, remote attacker to perform a username enumeration attack against an affected device. This vulnerability is due to differences in authentication responses that are sent back from the application as part of an authentication attempt. An attacker could exploit this vulnerability by sending authentication requests to an affected device. A successful exploit could allow the attacker to confirm existing user accounts, which could be used in further attacks. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
IBM Aspera Faspex 5.0.0 through 5.0.10 could disclose sensitive username information due to an observable response discrepancy.
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.
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.
An issue discovered in Elenos ETG150 FM transmitter v3.12 allows attackers to enumerate user accounts based on server responses when credentials are submitted.
Tadiran Telecom Aeonix - CWE-204: Observable Response Discrepancy
A vulnerability in the login functionality of the web application of ctrlX OS allows a remote unauthenticated attacker to guess valid usernames via multiple crafted HTTP requests.
A vulnerability in NetCat CMS allows an attacker to send a specially crafted http request that can be used to check whether a user exists in the system, which could be a basis for further attacks. This issue affects NetCat CMS v. 6.4.0.24126.2 and possibly others. Apply patch from vendor https://netcat.ru/ https://netcat.ru/] . Versions 6.4.0.24248 and on have the patch.
IBM Security QRadar EDR 3.12 could disclose sensitive information due to an observable login response discrepancy. IBM X-Force ID: 257697.
All CODESYS Visualization versions before V4.2.0.0 generate a login dialog vulnerable to information exposure allowing a remote, unauthenticated attacker to enumerate valid users.
SAP NetWeaver Server ABAP allows an unauthenticated attacker to exploit a vulnerability that causes the server to respond differently based on the existence of a specified user, potentially revealing sensitive information. This issue does not enable data modification and has no impact on server availability.
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.
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.
A vulnerability in Qlik Sense Enterprise on Windows could allow an remote attacker to enumerate domain user accounts. An attacker could exploit this vulnerability by sending authentication requests to an affected system. A successful exploit could allow the attacker to compare the response time that are returned by the affected system to determine which accounts are valid user accounts. Affected systems are only vulnerable if they have LDAP configured. The affected URI is /internal_forms_authentication/ the response time of the form is longer if the supplied user does not exists and shorter if the user exists.
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.
Rejetto HFS 3.0.0 through 3.2.0 returns observably different responses from its login endpoint depending on whether the submitted username exists. A remote unauthenticated attacker can use this to confirm valid account names, including the default admin account, facilitating password-guessing and session-forgery attacks.
Avaya IX Workforce Engagement v15.2.7.1195 - User Enumeration - Observable Response Discrepancy
IBM Aspera Console 3.3.0 through 3.4.8 could allow an attacker to enumerate usernames due to an observable response discrepancy.
IBM TXSeries for Multiplatforms 9.1 and 11.1 could allow an attacker to enumerate usernames due to an observable login attempt response discrepancy.
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.
User Enumeration via Discrepancies in Error Messages in the Celk Sistemas Celk Saude v.3.1.252.1 password recovery functionality which allows a remote attacker to enumerate users through discrepancies in the responses.
A vulnerability has been identified in Polarion V2310 (All versions), Polarion V2404 (All versions < V2404.2). The login implementation of the affected application contains an observable response discrepancy vulnerability when validating usernames. This could allow an unauthenticated remote attacker to distinguish between valid and invalid usernames.
IBM Aspera Orchestrator 4.0.1 could allow a remote attacker to enumerate usernames due to observable response discrepancies. IBM X-Force ID: 248545.
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.
xrdp is an open source RDP server. Versions 0.10.6 and prior contain a timing side-channel vulnerability in the login interface. Due to a discrepancy in response processing times, a remote attacker can infer the existence of a username on the system, leading to unauthorized information disclosure via username enumeration. This issue has been fixed in version 0.10.6.1.
ChurchCRM is an open-source church management system. In versions prior to 7.2.0, the public API login endpoint (/api/public/user/login) returns distinguishable HTTP response codes based on whether a username exists: 404 for non-existent users and 401 for valid users with incorrect passwords. An unauthenticated attacker can exploit this difference to enumerate valid usernames, with no rate limiting or account lockout to impede the process. This issue has been fixed in version 7.2.0.
Loway - CWE-204: Observable Response Discrepancy
Observable Response Discrepancy in SICK FTMg AIR FLOW SENSOR with Partnumbers 1100214, 1100215, 1100216, 1120114, 1120116, 1122524, 1122526 allows a remote attacker to gain information about valid usernames by analyzing challenge responses from the server via the REST interface.
Pimcore is an open source data & experience management platform. In versions prior to 10.1.3, it is possible to enumerate usernames via the forgot password functionality. This issue is fixed in version 10.1.3. As a workaround, one may apply the available patch manually.
web-auth/webauthn-lib is an open source set of PHP libraries and a Symfony bundle to allow developers to integrate that authentication mechanism into their web applications. The ProfileBasedRequestOptionsBuilder method returns allowedCredentials without any credentials if no username was found. When WebAuthn is used as the first or only authentication method, an attacker can enumerate usernames based on the absence of the `allowedCredentials` property in the assertion options response. This allows enumeration of valid or invalid usernames. By knowing which usernames are valid, attackers can focus their efforts on a smaller set of potential targets, increasing the efficiency and likelihood of successful attacks. This issue has been addressed in version 4.9.0 and all users are advised to upgrade. There are no known workarounds for this vulnerability.
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.
In Splunk Enterprise versions below 9.2.2, 9.1.5, and 9.0.10 and Splunk Cloud Platform versions below 9.1.2312.109, an attacker could determine whether or not another user exists on the instance by deciphering the error response that they would likely receive from the instance when they attempt to log in. This disclosure could then lead to additional brute-force password-guessing attacks. This vulnerability would require that the Splunk platform instance uses the Security Assertion Markup Language (SAML) authentication scheme.