CWE-204
Observable Response Discrepancy
Description
The product provides different responses to incoming requests in a way that reveals internal state information to an unauthorized actor outside of the intended control sphere.
Hierarchy (View 1000)
Parents
Children
none
Related attack patterns (CAPEC)
CAPEC-331 · CAPEC-332 · CAPEC-541 · CAPEC-580
CVEs mapped to this weakness (179)
page 3 of 9| CVE | Vendor / Product | Sev | Risk | CVSS | EPSS | KEV | Published | Description |
|---|---|---|---|---|---|---|---|---|
| CVE-2024-0391 | — | Med | 0.34 | 5.3 | 0.00 | May 11, 2026 | The check user account lock states feature within the email OTP flow fails to validate user input, allowing an attacker to infer the existence of registered user accounts. The discovery of valid usernames can increase the risk of brute-force and social engineering attacks.… | |
| CVE-2026-20195 | Med | 0.34 | 5.3 | 0.00 | May 6, 2026 | A vulnerability in an identity management API endpoint of Cisco ISE could allow an unauthenticated, remote attacker to enumerate valid user accounts on an affected device. This vulnerability exists because error messages are observed when the affected API endpoint is called.… | ||
| CVE-2025-3716 | Med | 0.34 | — | 0.00 | Mar 30, 2026 | User enumeration in ESET Protect (on-prem) via Response Timing. | ||
| CVE-2025-13460 | Med | 0.34 | 5.3 | 0.00 | Mar 16, 2026 | IBM Aspera Console 3.3.0 through 3.4.8 could allow an attacker to enumerate usernames due to an observable response discrepancy. | ||
| CVE-2026-26744 | Med | 0.34 | 5.3 | 0.00 | Feb 19, 2026 | A user enumeration vulnerability exists in FormaLMS 4.1.18 and below in the password recovery functionality accessible via the /lostpwd endpoint. The application returns different error messages for valid and invalid usernames allowing an unauthenticated attacker to determine… | ||
| CVE-2019-25338 | Med | 0.34 | 5.3 | 0.00 | Feb 12, 2026 | 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… | ||
| CVE-2026-24664 | Med | 0.34 | 5.3 | 0.00 | Feb 3, 2026 | The Open eClass platform (formerly known as GUnet eClass) is a complete course management system. Prior to version 4.2, a username enumeration vulnerability allows unauthenticated attackers to identify valid user accounts by analyzing differences in the login response behavior.… | ||
| CVE-2025-62181 | Med | 0.34 | 5.3 | 0.00 | Dec 10, 2025 | 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… | ||
| CVE-2025-40806 | Med | 0.34 | 5.3 | 0.00 | Dec 9, 2025 | 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… | ||
| CVE-2025-65899 | Med | 0.34 | 5.3 | 0.00 | Dec 4, 2025 | Kalmia CMS version 0.2.0 contains a user enumeration vulnerability in its authentication mechanism. The application returns different error messages for invalid users (user_not_found) versus valid users with incorrect passwords (invalid_password). This observable response… | ||
| CVE-2025-12994 | Med | 0.34 | 5.3 | 0.00 | Dec 4, 2025 | 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. | ||
| CVE-2025-59116 | Med | 0.34 | 5.3 | 0.00 | Nov 18, 2025 | Windu CMS is vulnerable to User Enumeration. This issue occurs during logon, where a difference in messages could allow an attacker to determine if the login is valid or not, enabling a brute force attack with valid logins. Only version 4.1 was tested and confirmed as… | ||
| CVE-2025-25236 | Med | 0.34 | 5.3 | 0.00 | Nov 12, 2025 | 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. | ||
| CVE-2025-62236 | Med | 0.34 | 5.3 | 0.00 | Oct 23, 2025 | The Frontier Airlines website has a publicly available endpoint that validates if an email addresses is associated with an account. An unauthenticated, remote attacker could determine valid email addresses, possibly aiding in further attacks. | ||
| CVE-2025-58586 | Med | 0.34 | 5.3 | 0.00 | Oct 6, 2025 | 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. | ||
| CVE-2025-56764 | Med | 0.34 | 5.3 | 0.00 | Sep 29, 2025 | Trivision NC-227WF firmware 5.80 (build 20141010) login mechanism reveals whether a username exists or not by returning different error messages ("Unknown user" vs. "Wrong password"), allowing an attacker to enumerate valid usernames. | ||
| CVE-2025-54834 | Med | 0.34 | 5.3 | 0.00 | Jul 31, 2025 | 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. | ||
| CVE-2025-52899 | Med | 0.34 | 5.3 | 0.00 | Jul 29, 2025 | Tuleap is an Open Source Suite created to facilitate management of software development and collaboration. In Tuleap Community Edition prior to version 16.9.99.1750843170 and Tuleap Enterprise Edition prior to 16.8-4 and 16.9-2, the forgot password form allows for user… | ||
| CVE-2025-27451 | Med | 0.34 | 5.3 | 0.00 | Jul 3, 2025 | 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. | ||
| CVE-2025-49187 | Med | 0.34 | 5.3 | 0.00 | Jun 12, 2025 | 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. |
- risk 0.34cvss 5.3epss 0.00
The check user account lock states feature within the email OTP flow fails to validate user input, allowing an attacker to infer the existence of registered user accounts. The discovery of valid usernames can increase the risk of brute-force and social engineering attacks.…
- risk 0.34cvss 5.3epss 0.00
A vulnerability in an identity management API endpoint of Cisco ISE could allow an unauthenticated, remote attacker to enumerate valid user accounts on an affected device. This vulnerability exists because error messages are observed when the affected API endpoint is called.…
- risk 0.34cvss —epss 0.00
User enumeration in ESET Protect (on-prem) via Response Timing.
- risk 0.34cvss 5.3epss 0.00
IBM Aspera Console 3.3.0 through 3.4.8 could allow an attacker to enumerate usernames due to an observable response discrepancy.
- risk 0.34cvss 5.3epss 0.00
A user enumeration vulnerability exists in FormaLMS 4.1.18 and below in the password recovery functionality accessible via the /lostpwd endpoint. The application returns different error messages for valid and invalid usernames allowing an unauthenticated attacker to determine…
- risk 0.34cvss 5.3epss 0.00
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…
- risk 0.34cvss 5.3epss 0.00
The Open eClass platform (formerly known as GUnet eClass) is a complete course management system. Prior to version 4.2, a username enumeration vulnerability allows unauthenticated attackers to identify valid user accounts by analyzing differences in the login response behavior.…
- risk 0.34cvss 5.3epss 0.00
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…
- risk 0.34cvss 5.3epss 0.00
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…
- risk 0.34cvss 5.3epss 0.00
Kalmia CMS version 0.2.0 contains a user enumeration vulnerability in its authentication mechanism. The application returns different error messages for invalid users (user_not_found) versus valid users with incorrect passwords (invalid_password). This observable response…
- risk 0.34cvss 5.3epss 0.00
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.
- risk 0.34cvss 5.3epss 0.00
Windu CMS is vulnerable to User Enumeration. This issue occurs during logon, where a difference in messages could allow an attacker to determine if the login is valid or not, enabling a brute force attack with valid logins. Only version 4.1 was tested and confirmed as…
- risk 0.34cvss 5.3epss 0.00
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.
- risk 0.34cvss 5.3epss 0.00
The Frontier Airlines website has a publicly available endpoint that validates if an email addresses is associated with an account. An unauthenticated, remote attacker could determine valid email addresses, possibly aiding in further attacks.
- risk 0.34cvss 5.3epss 0.00
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.
- risk 0.34cvss 5.3epss 0.00
Trivision NC-227WF firmware 5.80 (build 20141010) login mechanism reveals whether a username exists or not by returning different error messages ("Unknown user" vs. "Wrong password"), allowing an attacker to enumerate valid usernames.
- risk 0.34cvss 5.3epss 0.00
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.
- risk 0.34cvss 5.3epss 0.00
Tuleap is an Open Source Suite created to facilitate management of software development and collaboration. In Tuleap Community Edition prior to version 16.9.99.1750843170 and Tuleap Enterprise Edition prior to 16.8-4 and 16.9-2, the forgot password form allows for user…
- risk 0.34cvss 5.3epss 0.00
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.
- risk 0.34cvss 5.3epss 0.00
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.