CWE-204
Observable Response Discrepancy
Common consequences1
- ConfidentialityAccess ControlRead Application DataBypass Protection Mechanism
Potential mitigations2
- Architecture and Design
Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
- Implementation
Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success. If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages can be viewed by attackers. Highly sensitive information such as passwords should never be saved to log files. Avoid inconsistent messaging that might accidentally tip off an attacker about internal state, such as whether a user account exists or not.
Relationships1
- ChildOfCWE-203
CVEs referencing this CWE91
| CVE | Description | Severity | EPSS | Flags | Modified |
|---|---|---|---|---|---|
| CVE-2022-41697 | A user enumeration vulnerability exists in the login functionality of Ghost Foundation Ghost 5.9.4. A specially-crafted HTTP request can lead to a disclosure of sensitive information. An attacker can send a series of HTTP requests to trigger this vulnerability. | MEDIUM5.3 | 20%p97 | 2025-04-14 | |
| CVE-2016-9499 | Accellion FTP server prior to version FTA_9_12_220 only returns the username in the server response if the username is invalid. An attacker may use this information to determine valid user accounts and enumerate them. | NONE | 7.77%p94 | 2024-11-21 | |
| CVE-2019-19030 | Cloud Native Computing Foundation Harbor before 1.10.3 and 2.x before 2.0.1 allows resource enumeration because unauthenticated API calls reveal (via the HTTP status code) whether a resource exists. | MEDIUM5.3 | 1.89%p77 | PoC | 2025-04-14 |
| CVE-2021-20049 | A vulnerability in SonicWall SMA100 password change API allows a remote unauthenticated attacker to perform SMA100 username enumeration based on the server responses. This vulnerability impacts 10.2.1.2-24sv, 10.2.0.8-37sv and earlier 10.x versions. | HIGH7.5 | 1.35%p68 | 2024-11-21 | |
| CVE-2022-0564 | 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. | MEDIUM5.3 | 1.32%p67 | 2025-04-25 | |
| CVE-2021-39189 | 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. | MEDIUM5.3 | 1.24%p65 | 2024-11-21 | |
| CVE-2020-11063 | In TYPO3 CMS versions 10.4.0 and 10.4.1, it has been discovered that time-based attacks can be used with the password reset functionality for backend users. This allows an attacker to mount user enumeration based on email addresses assigned to backend user accounts. This has been fixed in 10.4.2. | LOW3.7 | 1.19%p64 | 2024-12-03 | |
| CVE-2024-39211 | 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. | MEDIUM5.3 | 1.15%p63 | PoC | 2026-04-15 |
| CVE-2021-34580 | In mymbCONNECT24, mbCONNECT24 <= 2.9.0 an unauthenticated user can enumerate valid backend users by checking what kind of response the server sends for crafted invalid login attempts. | HIGH7.5 | 1.00%p58 | 2024-11-21 | |
| CVE-2025-34255 | 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. | MEDIUM5.3 | 0.95%p57 | 2026-05-25 | |
| CVE-2025-34254 | 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. | MEDIUM5.3 | 0.95%p57 | 2026-05-25 | |
| CVE-2022-21659 | Flask-AppBuilder is an application development framework, built on top of the Flask web framework. In affected versions there exists a user enumeration vulnerability. This vulnerability allows for a non authenticated user to enumerate existing accounts by timing the response time from the server when you are logging in. Users are advised to upgrade to version 3.4.4 as soon as possible. There are no known workarounds for this issue. | MEDIUM5.3 | 0.94%p56 | 2025-05-05 | |
| CVE-2022-31248 | A Observable Response Discrepancy vulnerability in spacewalk-java of SUSE Manager Server 4.1, SUSE Manager Server 4.2 allows remote attackers to discover valid usernames. This issue affects: SUSE Manager Server 4.1 spacewalk-java versions prior to 4.1.46-1. SUSE Manager Server 4.2 spacewalk-java versions prior to 4.2.37-1. | MEDIUM5.3 | 0.87%p54 | 2024-11-21 | |
| CVE-2024-2482 | A vulnerability has been found in Surya2Developer Hostel Management Service 1.0 and classified as problematic. Affected by this vulnerability is an unknown functionality of the file /check_availability.php of the component HTTP POST Request Handler. The manipulation of the argument oldpassword leads to observable response discrepancy. The attack can be launched remotely. The complexity of an attack is rather high. The exploitation appears to be difficult. The exploit has been disclosed to the public and may be used. The associated identifier of this vulnerability is VDB-256891. | LOW3.7 | 0.83%p53 | 2025-01-23 | |
| CVE-2024-45231 | An issue was discovered in Django v5.1.1, v5.0.9, and v4.2.16. The django.contrib.auth.forms.PasswordResetForm class, when used in a view implementing password reset flows, allows remote attackers to enumerate user e-mail addresses by sending password reset requests and observing the outcome (only when e-mail sending is consistently failing). | MEDIUM5.3 | 0.81%p52 | 2025-03-17 | |
| CVE-2023-23449 | 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. | MEDIUM5.3 | 0.79%p51 | 2026-06-01 | |
| CVE-2022-22520 | 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. | MEDIUM5.3 | 0.79%p51 | 2024-11-21 | |
| CVE-2025-62512 | Piwigo is an open source photo gallery application for the web. In version 15.5.0 and likely earlier 15.x releases, the password reset functionality in Piwigo allows an unauthenticated attacker to determine whether a given username or email address exists in the system. The endpoint at password.php?action=lost returns distinct messages for valid vs. invalid accounts, enabling user enumeration. As of time of publication, no known patches are available. | MEDIUM5.3 | 0.77%p51 | 2026-02-27 | |
| CVE-2024-24766 | CasaOS-UserService provides user management functionalities to CasaOS. Starting in version 0.4.4.3 and prior to version 0.4.7, the Casa OS Login page disclosed the username enumeration vulnerability in the login page. An attacker can enumerate the CasaOS username using the application response. If the username is incorrect application gives the error `**User does not exist**`. If the password is incorrect application gives the error `**Invalid password**`. Version 0.4.7 fixes this issue. | HIGH7.5 | 0.76%p50 | 2025-05-28 | |
| CVE-2022-20633 | 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. | MEDIUM5.3 | 0.75%p50 | 2025-07-31 | |
| CVE-2021-38476 | InHand Networks IR615 Router's Versions 2.3.0.r4724 and 2.3.0.r4870 authentication process response indicates and validates the existence of a username. This may allow an attacker to enumerate different user accounts. | MEDIUM5.3 | 0.74%p50 | 2024-11-21 | |
| CVE-2024-13028 | A vulnerability, which was classified as problematic, has been found in Antabot White-Jotter up to 0.2.2. This issue affects some unknown processing of the file /login. The manipulation of the argument username leads to observable response discrepancy. The attack may be initiated remotely. The complexity of an attack is rather high. The exploitation is known to be difficult. The exploit has been disclosed to the public and may be used. | LOW3.7 | 0.73%p49 | 2025-08-21 | |
| CVE-2026-21484 | AnythingLLM is an application that turns pieces of content into context that any LLM can use as references during chatting. Prior to commit e287fab56089cf8fcea9ba579a3ecdeca0daa313, the password recovery endpoint returns different error messages depending on whether a username exists, so enabling username enumeration. Commit e287fab56089cf8fcea9ba579a3ecdeca0daa313 fixes this issue. | MEDIUM5.3 | 0.71%p49 | 2026-02-23 | |
| CVE-2024-36510 | An observable response discrepancy vulnerability [CWE-204] in FortiClientEMS 7.4.0, 7.2.0 through 7.2.4, 7.0 all versions, and FortiSOAR 7.5.0, 7.4.0 through 7.4.4, 7.3.0 through 7.3.2, 7.2 all versions, 7.0 all versions, 6.4 all versions may allow an unauthenticated attacker to enumerate valid users via observing login request responses. | MEDIUM5.3 | 0.70%p48 | 2025-01-31 | |
| CVE-2022-1989 | 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. | MEDIUM5.3 | 0.69%p48 | 2024-11-21 | |
| CVE-2025-1101 | 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. | MEDIUM5.3 | 0.68%p48 | 2025-10-24 | |
| CVE-2024-13198 | A vulnerability classified as problematic has been found in langhsu Mblog Blog System 3.5.0. Affected is an unknown function of the file /login. The manipulation leads to observable response discrepancy. It is possible to launch the attack remotely. The complexity of an attack is rather high. The exploitability is told to be difficult. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way. | LOW3.7 | 0.67%p47 | 2025-09-24 | |
| CVE-2024-6056 | A vulnerability was found in nasirkhan Laravel Starter up to 11.8.0. It has been rated as problematic. Affected by this issue is some unknown functionality of the file /forgot-password of the component Password Reset Handler. The manipulation of the argument Email leads to observable response discrepancy. The attack may be launched remotely. The complexity of an attack is rather high. The exploitation is known to be difficult. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-268784. NOTE: The vendor was contacted early about this disclosure but did not respond in any way. | MEDIUM5.3 | 0.65%p46 | 2024-11-21 | |
| CVE-2026-28288 | Dify is an open-source LLM app development platform. Prior to 1.9.0, responses from the Dify API to existing and non-existent accounts differ, allowing an attacker to enumerate email addresses registered with Dify. Version 1.9.0 fixes the issue. | MEDIUM5.3 | 0.64%p46 | 2026-03-09 | |
| CVE-2023-1540 | Observable Response Discrepancy in GitHub repository answerdev/answer prior to 1.0.6. | MEDIUM5.3 | 0.64%p46 | 2025-02-25 | |
| CVE-2024-28232 | Go package IceWhaleTech/CasaOS-UserService provides user management functionalities to CasaOS. The Casa OS Login page has disclosed the username enumeration vulnerability in the login page which was patched in version 0.4.7. This issue in CVE-2024-28232 has been patched in version 0.4.8 but that version has not yet been uploaded to Go's package manager. | HIGH7.5 | 0.62%p45 | 2025-06-24 | |
| CVE-2026-28358 | NocoDB is software for building databases as spreadsheets. Prior to version 0.301.3, the password forgot endpoint returned different responses for registered and unregistered emails, allowing user enumeration. This issue has been patched in version 0.301.3. | MEDIUM5.3 | 0.60%p44 | 2026-03-03 | |
| CVE-2025-34155 | Tibbo AggreGate Network Manager < 6.40.05 contains an observable response discrepancy in its login functionality. Authentication failure messages differ based on whether a supplied username exists or not, allowing an unauthenticated remote attacker to infer valid account identifiers. This can facilitate user enumeration and increase the likelihood of targeted brute-force or credential-stuffing attacks. | NONE | 0.59%p44 | 2026-05-14 | |
| CVE-2024-25146 | Liferay Portal 7.2.0 through 7.4.1, and older unsupported versions, and Liferay DXP 7.3 before service pack 3, 7.2 before fix pack 18, and older unsupported versions returns with different responses depending on whether a site does not exist or if the user does not have permission to access the site, which allows remote attackers to discover the existence of sites by enumerating URLs. This vulnerability occurs if locale.prepend.friendly.url.style=2 and if a custom 404 page is used. | MEDIUM5.3 | 0.59%p44 | 2026-03-19 | |
| CVE-2022-39228 | vantage6 is a privacy preserving federated learning infrastructure for secure insight exchange. vantage6 does not inform the user of wrong username/password combination if the username actually exists. This is an attempt to prevent bots from obtaining usernames. However, if a wrong password is entered a number of times, the user account is blocked temporarily. This issue has been fixed in version 3.8.0. | MEDIUM6.5 | 0.59%p44 | 2026-05-29 | |
| CVE-2022-39315 | Kirby is a Content Management System. Prior to versions 3.5.8.2, 3.6.6.2, 3.7.5.1, and 3.8.1, a user enumeration vulnerability affects all Kirby sites with user accounts unless Kirby's API and Panel are disabled in the config. It can only be exploited for targeted attacks because the attack does not scale to brute force. The problem has been patched in Kirby 3.5.8.2, Kirby 3.6.6.2, Kirby 3.7.5.1, and Kirby 3.8.1. In all of the mentioned releases, the maintainers have rewritten the affected code so that the delay is also inserted after the brute force limit is reached. | MEDIUM5.3 | 0.59%p43 | 2025-04-23 | |
| CVE-2025-23214 | 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. | NONE | 0.58%p43 | 2026-04-15 | |
| CVE-2023-35698 | 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. | MEDIUM5.3 | 0.57%p43 | 2026-06-01 | |
| CVE-2024-40627 | 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. | MEDIUM5.8 | 0.56%p42 | 2026-04-15 | |
| CVE-2018-25350 | userSpice 4.3.24 contains a username enumeration vulnerability that allows unauthenticated attackers to discover valid usernames by sending POST requests to the existingUsernameCheck.php endpoint. Attackers can submit usernames and analyze response text for the 'taken' string to identify existing accounts in the system. | CRITICAL9.8 | 0.54%p41 | 2026-05-26 | |
| CVE-2023-32346 | 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. | MEDIUM5.3 | 0.54%p41 | 2025-01-16 | |
| CVE-2023-23584 | An observable response discrepancy in the Gallagher Command Centre RESTAPI allows an insufficiently-privileged user to infer the presence of items that would not otherwise be viewable. This issue affects: Gallagher Command Centre 8.70 prior to vEL8.70.1787 (MR2), 8.60 prior to vEL8.60.2039 (MR4), all version of 8.50 and prior. | MEDIUM4.3 | 0.50%p39 | 2024-11-21 | |
| CVE-2023-39343 | Sulu is an open-source PHP content management system based on the Symfony framework. It allows over the Admin Login form to detect which user (username, email) exists and which one do not exist. Sulu Installation not using the old Symfony 5.4 security System and previous version are not impacted by this Security issue. The vulnerability has been patched in version 2.5.10. | MEDIUM4.3 | 0.50%p38 | 2024-11-21 | |
| CVE-2021-36201 | Under certain circumstances a CCURE Portal user could enumerate user accounts in CCURE 9000 version 2.90 and prior versions. | MEDIUM5.3 | 0.50%p39 | 2025-05-15 | |
| CVE-2024-1145 | User enumeration vulnerability in Devklan's Alma Blog that affects versions 2.1.10 and earlier. This vulnerability could allow a remote user to retrieve all valid users registered in the application just by looking at the request response. | MEDIUM5.3 | 0.49%p38 | 2025-10-15 | |
| CVE-2025-24980 | 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. | MEDIUM5.3 | 0.48%p38 | 2026-01-16 | |
| CVE-2023-28412 | 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. | MEDIUM5.3 | 0.48%p38 | 2025-01-16 | |
| CVE-2025-54834 | OPEXUS FOIAXpress Public Access Link (PAL) version v11.1.0 allows an unauthenticated, remote attacker to query the /App/CreateRequest.aspx endpoint to check for the existence of valid usernames. There are no rate-limiting mechanisms in place. | MEDIUM5.3 | 0.47%p37 | 2026-01-23 | |
| CVE-2023-27283 | IBM Aspera Orchestrator 4.0.1 could allow a remote attacker to enumerate usernames due to observable response discrepancies. IBM X-Force ID: 248545. | MEDIUM5.3 | 0.47%p37 | 2025-01-07 | |
| CVE-2023-38362 | 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. | MEDIUM5.3 | 0.47%p37 | 2025-01-07 | |
| CVE-2021-20556 | 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. | MEDIUM5.3 | 0.46%p36 | 2025-01-07 | |
| CVE-2023-37831 | An issue discovered in Elenos ETG150 FM transmitter v3.12 allows attackers to enumerate user accounts based on server responses when credentials are submitted. | MEDIUM5.3 | 0.46%p36 | 2024-11-21 | |
| CVE-2023-41885 | 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. | MEDIUM5.3 | 0.46%p36 | 2024-11-21 | |
| CVE-2023-3221 | 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. | MEDIUM5.3 | 0.46%p36 | 2024-11-21 | |
| CVE-2023-3336 | 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. | MEDIUM5.3 | 0.46%p36 | 2024-11-21 | |
| CVE-2023-27464 | 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. | MEDIUM5.3 | 0.46%p36 | 2025-02-07 | |
| CVE-2024-34336 | User enumeration vulnerability in ORDAT FOSS-Online before v2.24.01 allows attackers to determine if an account exists in the application by comparing the server responses of the forgot password functionality. | MEDIUM5.3 | 0.45%p36 | 2024-09-18 | |
| CVE-2024-28868 | 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. | MEDIUM5.3 | 0.45%p36 | 2025-02-12 | |
| CVE-2023-46170 | IBM DS8900F HMC 89.21.19.0, 89.21.31.0, 89.30.68.0, 89.32.40.0, and 89.33.48.0 could allow an authenticated user to arbitrarily read files after enumerating file names. | MEDIUM6.5 | 0.45%p36 | 2025-03-11 | |
| CVE-2023-31186 | Avaya IX Workforce Engagement v15.2.7.1195 - User Enumeration - Observable Response Discrepancy | MEDIUM5.3 | 0.45%p36 | 2025-01-10 | |
| CVE-2023-49069 | 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. | MEDIUM5.3 | 0.44%p35 | 2026-04-15 | |
| CVE-2025-31124 | 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. | MEDIUM5.3 | 0.43%p34 | 2025-08-26 | |
| CVE-2024-55198 | 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. | MEDIUM5.3 | 0.42%p33 | 2025-04-03 | |
| CVE-2024-12663 | A vulnerability classified as problematic was found in funnyzpc Mee-Admin up to 1.6. This vulnerability affects unknown code of the file /mee/login of the component Login. The manipulation of the argument username leads to observable response discrepancy. The attack can be initiated remotely. The complexity of an attack is rather high. The exploitation appears to be difficult. The exploit has been disclosed to the public and may be used. | LOW3.7 | 0.42%p33 | 2026-04-15 | |
| CVE-2024-8651 | 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. | MEDIUM5.3 | 0.42%p33 | 2024-09-23 | |
| CVE-2019-25338 | DokuWiki 2018-04-22b contains a username enumeration vulnerability in its password reset functionality that allows attackers to identify valid user accounts. Attackers can submit different usernames to the password reset endpoint and distinguish between existing and non-existing accounts by analyzing the server's error response messages. | MEDIUM5.3 | 0.41%p32 | 2026-03-05 | |
| CVE-2025-62181 | Pega Platform versions 7.1.0 through Infinity 25.1.0 are affected by a User Enumeration. This issue occurs during user authentication process, where a difference in response time could allow a remote unauthenticated user to determine if a username is valid or not. This only applies to deprecated basic-authentication feature and other more secure authentication mechanisms are recommended. A fix is being provided in the 24.1.4, 24.2.4, and 25.1.1 patch releases. Please note: Basic credentials authentication service type is deprecated started in 24.2 version: https://docs.pega.com/bundle/platform/page/platform/release-notes/security/whats-new-security-242.html. | MEDIUM5.3 | 0.41%p32 | 2026-04-15 | |
| CVE-2025-3092 | An unauthenticated remote attacker can enumerate valid user names from an unprotected endpoint. | HIGH7.5 | 0.41%p33 | 2026-04-15 | |
| CVE-2024-38322 | IBM Storage Defender - Resiliency Service 2.0.0 through 2.0.4 agent username and password error response discrepancy exposes product to brute force enumeration. IBM X-Force ID: 294869. | HIGH7.5 | 0.41%p32 | 2024-11-21 | |
| CVE-2024-51447 | 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. | MEDIUM5.3 | 0.40%p31 | 2025-08-22 | |
| CVE-2026-33419 | MinIO is a high-performance object storage system. Prior to RELEASE.2026-03-17T21-25-16Z, MinIO AIStor's STS (Security Token Service) AssumeRoleWithLDAPIdentity endpoint is vulnerable to LDAP credential brute-forcing due to two combined weaknesses: (1) distinguishable error responses that enable username enumeration, and (2) absence of rate limiting on authentication attempts. An unauthenticated network attacker can enumerate valid LDAP usernames and then perform unlimited password guessing to obtain temporary AWS-style STS credentials, gaining access to the victim's S3 buckets and objects. This issue has been patched in RELEASE.2026-03-17T21-25-16Z. | HIGH7.5 | 0.39%p31 | 2026-04-08 | |
| CVE-2025-5485 | 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. | HIGH8.6 | 0.39%p31 | 2026-04-15 | |
| CVE-2024-39912 | 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. | MEDIUM5.3 | 0.39%p31 | 2026-04-15 | |
| CVE-2025-40806 | 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. | MEDIUM5.3 | 0.38%p29 | 2026-01-02 | |
| CVE-2024-33856 | An issue was discovered in Logpoint before 7.4.0. An attacker can enumerate a valid list of usernames by observing the response time at the Forgot Password endpoint. | MEDIUM5.3 | 0.38%p30 | 2025-04-18 | |
| CVE-2023-4095 | 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. | MEDIUM5.3 | 0.38%p29 | 2024-11-21 | |
| CVE-2023-40179 | 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. | MEDIUM5.3 | 0.38%p29 | 2024-11-21 | |
| CVE-2023-37217 | Tadiran Telecom Aeonix - CWE-204: Observable Response Discrepancy | MEDIUM5.3 | 0.38%p29 | 2024-11-21 | |
| CVE-2025-61907 | Icinga 2 is an open source monitoring system. In Icinga 2 versions 2.4 through 2.15.0, filter expressions provided to the various /v1/objects endpoints could access variables or objects that would otherwise be inaccessible for the user. This allows authenticated API users to learn information that should be hidden from them, including global variables not permitted by the variables permission and objects not permitted by the corresponding objects/query permissions. The vulnerability is fixed in versions 2.15.1, 2.14.7, and 2.13.13. | MEDIUM6.5 | 0.37%p28 | 2025-11-26 | |
| CVE-2025-9109 | A security flaw has been discovered in Portabilis i-Diario up to 1.5.0. Affected by this vulnerability is an unknown functionality of the file /password/email of the component Password Recovery Endpoint. The manipulation results in observable response discrepancy. It is possible to launch the attack remotely. This attack is characterized by high complexity. The exploitation appears to be difficult. The exploit has been released to the public and may be exploited. | LOW3.7 | 0.37%p28 | 2026-04-29 | |
| CVE-2025-30280 | 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. | MEDIUM5.3 | 0.37%p29 | 2026-04-15 | |
| CVE-2026-4113 | An observable response discrepancy vulnerability in the SonicWall SMA1000 series appliances allows a remote attacker to enumerate SSL VPN user credentials. | HIGH7.2 | 0.36%p28 | 2026-05-14 | |
| CVE-2026-23511 | ZITADEL is an open source identity management platform. Prior to 4.9.1 and 3.4.6, a user enumeration vulnerability has been discovered in Zitadel's login interfaces. An unauthenticated attacker can exploit this flaw to confirm the existence of valid user accounts by iterating through usernames and userIDs. This vulnerability is fixed in 4.9.1 and 3.4.6. | MEDIUM5.3 | 0.36%p28 | 2026-01-26 | |
| CVE-2025-69413 | In Gitea before 1.25.2, /api/v1/user has different responses for failed authentication depending on whether a username exists. | MEDIUM5.3 | 0.36%p27 | 2026-01-06 | |
| CVE-2023-33859 | IBM Security QRadar EDR 3.12 could disclose sensitive information due to an observable login response discrepancy. IBM X-Force ID: 257697. | MEDIUM5.3 | 0.36%p28 | 2024-11-21 | |
| CVE-2026-27480 | Static Web Server (SWS) is a production-ready web server suitable for static web files or assets. In versions 2.1.0 through 2.40.1, a timing-based username enumeration vulnerability in Basic Authentication allows attackers to identify valid users by exploiting early responses for invalid usernames, enabling targeted brute-force or credential-stuffing attacks. SWS checks whether a username exists before verifying the password, causing valid usernames to follow a slower code path (e.g., bcrypt hashing) while invalid usernames receive an immediate 401 response. This timing discrepancy allows attackers to enumerate valid accounts by measuring response-time differences. This issue has been fixed in version 2.41.0. | MEDIUM5.3 | 0.35%p27 | 2026-02-24 | |
| CVE-2026-25509 | CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to version 0.28.5.0, the authentication implementation in CI4MS is vulnerable to email enumeration. An unauthenticated attacker can determine whether an email address is registered in the system by analyzing the application's response during the password reset process. This issue has been patched in version 0.28.5.0. | MEDIUM5.3 | 0.35%p27 | 2026-02-11 | |
| CVE-2025-24342 | 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. | MEDIUM5.3 | 0.35%p27 | 2026-04-15 | |
| CVE-2024-35114 | IBM Control Center 6.2.1 and 6.3.1 could allow a remote attacker to enumerate usernames due to an observable discrepancy between login attempts. | MEDIUM5.3 | 0.35%p26 | 2025-11-06 | |
| CVE-2024-38431 | Matrix Tafnit v8 - CWE-204: Observable Response Discrepancy | HIGH7.5 | 0.35%p27 | 2024-11-21 | |
| CVE-2022-39314 | Kirby is a flat-file CMS. In versions prior to 3.5.8.2, 3.6.6.2, 3.7.5.1, and 3.8.1, Kirby is subject to user enumeration due to Improper Restriction of Excessive Authentication Attempts. This vulnerability affects you only if you are using the `code` or `password-reset` auth method with the `auth.methods` option or if you have enabled the `debug` option in production. By using two or more IP addresses and multiple login attempts, valid user accounts will lock, but invalid accounts will not, leading to account enumeration. This issue has been patched in versions 3.5.8.2, 3.6.6.2, 3.7.5.1, and 3.8.1. If you cannot update immediately, you can work around the issue by setting the `auth.methods` option to `password`, which disables the code-based login and password reset forms. | LOW3.7 | 0.35%p27 | 2026-01-30 |