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.

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.

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.

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.

IBM i 7.2, 7.3, 7.4, and 7.5 Service Tools Server (SST) is vulnerable to SST user enumeration by a remote attacker. This vulnerability can be used by a malicious actor to gather information about SST users that can be targeted in further attacks. IBM X-Force ID: 287538.

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.

In Logpoint before 7.4.0, an attacker can enumerate a valid list of usernames by using publicly exposed URLs of shared widgets.

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.

User enumeration can occur in the Authentication REST API in Delinea PAM Secret Server 11.4. This allows a remote attacker to determine whether a user is valid because of a difference in responses from the /oauth2/token endpoint.

Proxmox VE prior to 3.2: 'AccessControl.pm' User Enumeration Vulnerability

HCL Aftermarket EPC is vulnerable to attack since It was found that a malicious actor can use brute-force techniques to either guess or confirm valid users in the system. Use renumeration is when a malicious actor can use brute-force techniques to either guess or confirm valid users in a system

An user enumeration vulnerability was found in SEO Panel 4.10.0. This issue occurs during user authentication, where a difference in error messages could allow an attacker to determine if a username is valid or not, enabling a brute-force attack with valid usernames.

Jenkins Generic Webhook Trigger Plugin 1.84.1 and earlier uses a non-constant time comparison function when checking whether the provided and expected webhook token are equal, potentially allowing attackers to use statistical methods to obtain a valid webhook token.

Fixed in v1.5.1, Argo version v1.5.0 was vulnerable to a user-enumeration vulnerability which allowed attackers to determine the usernames of valid (non-SSO) accounts because /api/v1/session returned 401 for an existing username and 404 otherwise.

The login mechanism of Sage DPW 2021_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 behavior in newer versions.

The private-key operations in ecc.c in wolfSSL before 4.4.0 do not use a constant-time modular inverse when mapping to affine coordinates, aka a "projective coordinates leak."

djangoSIGE through 1.10 (commit a6fe7e8) contains a user enumeration vulnerability in ForgotPasswordView within djangosige/apps/login/views.py that allows unauthenticated attackers to identify valid accounts by observing distinct error messages returned by the password reset endpoint. Attackers can submit arbitrary usernames or email addresses to the POST login/esqueceu/ endpoint and distinguish between existing and non-existing accounts based on observable discrepancies in the application's responses.

In BIG-IP 15.0.0, 14.1.0-14.1.0.6, 14.0.0-14.0.0.5, 13.0.0-13.1.1.5, 12.1.0-12.1.4.1, 11.5.1-11.6.4, BIG-IQ 7.0.0, 6.0.0-6.1.0,5.2.0-5.4.0, iWorkflow 2.3.0, and Enterprise Manager 3.1.1, the Configuration utility login page may not follow best security practices when handling a malicious request.

IBM Guardium Data Encryption (GDE) 5.0.0.2 behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor, which could facilitate username enumeration. IBM X-Force ID: 213856.

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.

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.

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.

An issue was discovered in Symfony 4.2.0 to 4.2.11 and 4.3.0 to 4.3.7. The ability to enumerate users was possible due to different handling depending on whether the user existed when making unauthorized attempts to use the switch users functionality. This is related to symfony/security.

The Reset Password feature in Pagekit 1.0.17 gives a different response depending on whether the e-mail address of a valid user account is entered, which might make it easier for attackers to enumerate accounts.

An issue was discovered in ConnectWise Control (formerly known as ScreenConnect) 19.3.25270.7185. There is a user enumeration vulnerability, allowing an unauthenticated attacker to determine with certainty if an account exists for a given username.

The HCL Domino AppDev Pack IAM service is susceptible to a User Account Enumeration vulnerability.   During a failed login attempt a difference in messages could allow an attacker to determine if the user is valid or not.  The attacker could use this information to focus a brute force attack on valid users.

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 discrepancy allows unauthenticated attackers to enumerate valid usernames on the system.

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.

The Page Restriction WordPress (WP) – Protect WP Pages/Post plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 1.3.6 via the WordPress core search feature. This makes it possible for unauthenticated attackers to extract sensitive data from posts that have been restricted to higher-level roles such as administrator.

Dropbear 2011.54 through 2018.76 has an inconsistent failure delay that may lead to revealing valid usernames, a different issue than CVE-2018-15599.

In CentOS-WebPanel.com (aka CWP) CentOS Web Panel 0.9.8.846, the Login process allows attackers to check whether a username is valid by reading the HTTP response.

CyberArk Identity 21.5.131, when handling an invalid authentication attempt, sometimes reveals whether the username is valid. In certain authentication policy configurations with MFA, the API response length can be used to differentiate between a valid user and an invalid one (aka Username Enumeration). Response differentiation enables attackers to enumerate usernames of valid application users. Attackers can use this information to leverage brute-force and dictionary attacks in order to discover valid account information such as passwords.

Under certain circumstances a CCURE Portal user could enumerate user accounts in CCURE 9000 version 2.90 and prior versions.

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.

Frappe is a full-stack web application framework. Prior to 16.16.0 and 15.106.0, user enumeration could be performed via the reset_password endpoint. This issue is fixed in versions 16.16.0 and 15.106.0.

Cap-go before 12.128.2 contains an information disclosure vulnerability in the OPTIONS /build/upload/:jobId/* endpoint that allows unauthenticated attackers to enumerate valid builder job IDs through observable response discrepancies. Attackers can probe the endpoint without authentication to distinguish valid job IDs from invalid ones and generate sustained unauthenticated traffic for resource consumption.

Capgo before 12.128.2 contains an information disclosure vulnerability in the public.invite_user_to_org RPC function that allows unauthenticated attackers to enumerate organization existence by observing distinct error responses. Attackers can call the SECURITY DEFINER function with a publishable API key to determine if an organization ID exists based on NO_ORG versus NO_RIGHTS responses, enabling tenant enumeration attacks.

GLPI 9.5.7 contains a username enumeration vulnerability in the lost password recovery mechanism that allows attackers to validate email addresses. Attackers can systematically test email addresses by submitting requests to the password reset endpoint and analyzing response differences to identify valid user accounts.

MCO is vulnerable to User Enumeration through authentication-related functionalities. The application returns distinguishable responses for valid and invalid users during username reminder and password reset operations. An attacker can leverage these differences to enumerate valid usernames and email addresses. Because vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 25.3.3.1 but may also affect other versions.

IBM Security Identity Manager 7.0.2 could allow a remote user to enumerate usernames due to a difference of responses from valid and invalid login attempts. IBM X-Force ID: 200018

Ghost is a Node.js content management system. From 5.18.0 until 6.21.1, a discrepancy in responses from the members signin endpoints made it possible for an unauthenticated attacker to determine whether a given email address belongs to a registered member of a Ghost site. This vulnerability is fixed in 6.21.1.

Timing difference in password reset in Ergon Informatik AG's Airlock IAM 7.7.9, 8.0.8, 8.1.7, 8.2.4 and 8.3.1 allows unauthenticated attackers to enumerate usernames.

NocoDB is software for building databases as spreadsheets. Prior to 2026.05.1, the shared-view password check fell back to strict-equality (===) comparison for legacy plaintext passwords, leaking the password's length and per-character prefix through response timing. This vulnerability is fixed in 2026.05.1.

In Directus 8.x through 8.8.1, an attacker can discover whether a user is present in the database through the password reset feature. NOTE: This vulnerability only affects products that are no longer supported by the maintainer

In Bromite through 78.0.3904.130, there are adblock rules in the release APK; therefore, probing which resources are blocked and which aren't can identify the application version and defeat the User-Agent protection mechanism.

A username enumeration vulnerability exists in multiple WSO2 products when Multi-Attribute Login is enabled. In this configuration, the system returns a distinct "User does not exist" error message to the login form, regardless of the validate_username setting. This behavior allows malicious actors to determine which usernames exist in the system based on observable discrepancies in the application's responses. Exploitation of this vulnerability could aid in brute-force attacks, targeted phishing campaigns, or other social engineering techniques by confirming the validity of user identifiers within the system.

_account_forgot_password.ajax.php in MFScripts YetiShare 3.5.2 through 4.5.3 takes a different amount of time to return depending on whether an email address is configured for the account name provided. This can be used by an attacker to enumerate accounts by guessing email addresses.

In the Voatz application 2020-01-01 for Android, the amount of data transmitted during a single voter's vote depends on the different lengths of the metadata across the available voting choices, which makes it easier for remote attackers to discover this voter's choice by sniffing the network. For example, a small amount of sniffed data may indicate that a vote was cast for the candidate with the least metadata. An active man-in-the-middle attacker can leverage this behavior to disrupt voters' abilities to vote for a candidate opposed by the attacker.

Observable Timing Discrepancy in GitHub repository answerdev/answer prior to 1.0.6.

Observable Response Discrepancy in GitHub repository answerdev/answer prior to 1.0.6.