The Stop User Enumeration WordPress plugin before version 1.7.3 blocks REST API /wp-json/wp/v2/users/ requests for non-authorized users. However, this can be bypassed by URL-encoding the API path.

In Legion of the Bouncy Castle BC before 1.61 and BC-FJA before 1.0.1.2, attackers can obtain sensitive information about a private exponent because of Observable Differences in Behavior to Error Inputs. This occurs in org.bouncycastle.crypto.encodings.OAEPEncoding. Sending invalid ciphertext that decrypts to a short payload in the OAEP Decoder could result in the throwing of an early exception, potentially leaking some information about the private exponent of the RSA private key performing the encryption.

An issue was discovered in eGroupWare 17.1.20190111. A User Enumeration vulnerability exists under calendar/freebusy.php, which allows unauthenticated remote attackers to enumerate the users of web applications based on server response.

A vulnerability in Cisco Integrated Management Controller could allow an unauthenticated, remote attacker to enumerate valid usernames within the vulnerable application. The vulnerability is due to differences in authentication responses sent back from the application as part of an authentication attempt. An attacker could exploit this vulnerability by sending authentication requests to the affected application. A successful exploit could allow the attacker to confirm the names of administrative user accounts for use in further attacks.There are no workarounds that address this vulnerability.

Pritunl 1.29.2145.25 allows attackers to enumerate valid VPN usernames via a series of /auth/session login attempts. Initially, the server will return error 401. However, if the username is valid, then after 20 login attempts, the server will start responding with error 400. Invalid usernames will receive error 401 indefinitely. Note: This has been disputed by the vendor as not a vulnerability. They argue that this is an intended design

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.

NVIDIA BMC contains a vulnerability in IPMI handler, where an unauthorized attacker can use certain oracles to guess a valid BMC username, which may lead to an information disclosure.

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.

An issue was discovered in OpenSlides before 4.2.5. During login at the /system/auth/login/ endpoint, the system's response times differ depending on whether a user exists in the system. The timing discrepancy stems from the omitted hashing of the password (e.g., more than 100 milliseconds).

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 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.

Username enumeration is possible through Bypassing CAPTCHA in On-premise SureMDM Solution on Windows deployment allows attacker to enumerate local user information via error message. This issue affects SureMDM On-premise: 6.31 and below version

The commit 3730880 (April 2023) and v.0.9-beta1 of gugoan Economizzer has a user enumeration vulnerability in the login and forgot password functionalities. The app reacts differently when a user or email address is valid, and when it's not. This may allow an attacker to determine whether a user or email address is valid, or brute force valid usernames and email addresses.

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

An issue was discovered in the ProofreadPage (aka Proofread Page) extension for MediaWiki through 1.39.3. In includes/Page/PageContentHandler.php and includes/Page/PageDisplayHandler.php, hidden users can be exposed via public interfaces.

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.

The login functionality of the web server in affected devices does not normalize the response times of login attempts. An unauthenticated remote attacker could exploit this side-channel information to distinguish between valid and invalid usernames.

The login function of Mealie v1.0.0beta-2 allows attackers to enumerate existing usernames by timing the server's response time.

_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.

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.

A vulnerability in the External Interface of OTRS allows conclusions to be drawn about the existence of user accounts through different HTTP response codes and messages. This enables an attacker to systematically identify valid email addresses. This issue affects: * OTRS 7.0.X * OTRS 8.0.X * OTRS 2023.X * OTRS 2024.X * OTRS 2025.X

AMI BMC contains a vulnerability in the IPMI handler, where an unauthorized attacker can use certain oracles to guess a valid username, which may lead to information disclosure.

A vulnerability classified as problematic has been found in Rotem Dynamics Rotem CRM up to 20230729. This affects an unknown part of the file /LandingPages/api/otp/send?id=[ID][ampersand]method=sms of the component OTP URI Interface. The manipulation leads to information exposure through discrepancy. It is possible to initiate the attack remotely. The identifier VDB-233253 was assigned to this vulnerability. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.

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.

HashiCorp's Vault and Vault Enterprise are vulnerable to user enumeration when using the LDAP auth method. An attacker may submit requests of existent and non-existent LDAP users and observe the response from Vault to check if the account is valid on the LDAP server. This vulnerability is fixed in Vault 1.14.1 and 1.13.5.

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.

emoncms v11 and later was discovered to contain an information disclosure vulnerability which allows attackers to obtain the web directory path and other information leaked by the server via a crafted web request.

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.

SPIP before 3.1.11 and 3.2 before 3.2.5 provides different error messages from the password-reminder page depending on whether an e-mail address exists, which might help attackers to enumerate subscribers.

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.

On Coldcard MK1 and MK2 devices, a side channel for the row-based OLED display was found. The power consumption of each row-based display cycle depends on the number of illuminated pixels, allowing a partial recovery of display contents. For example, a hardware implant in the USB cable might be able to leverage this behavior to recover confidential secrets such as the PIN and BIP39 mnemonic. In other words, the side channel is relevant only if the attacker has enough control over the device's USB connection to make power-consumption measurements at a time when secret data is displayed. The side channel is not relevant in other circumstances, such as a stolen device that is not currently displaying secret data. On Coldcard MK1 and MK2 devices, a side channel for the row-based OLED display was found. The power consumption of each row-based display cycle depends on the number of illuminated pixels, allowing a partial recovery of display contents. For example, a hardware implant in the USB cable might be able to leverage this behavior to recover confidential secrets such as the PIN and BIP39 mnemonic. In other words, the side channel is relevant only if the attacker has enough control over the device's USB connection to make power-consumption measurements at a time when secret data is displayed. The side channel is not relevant in other circumstances, such as a stolen device that is not currently displaying secret data. NOTE: At Coinkite, we’ve already mitigated it, even though we feel strongly that it is not a legitimate issue. In our opinion, it is both unproven (might not even work) and also completely impractical—even if it could be made to work perfectly

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.

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.

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

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.

Tor Browser before 8.0.1 has an information exposure vulnerability. It allows remote attackers to detect the browser's UI locale by measuring a button width, even if the user has a "Don't send my language" setting.

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.

Dependency-Track is a Component Analysis platform that allows organizations to identify and reduce risk in the software supply chain. Performing a login request against the /api/v1/user/login endpoint with a username that exist in the system takes significantly longer than performing the same action with a username that is not known by the system. The observable difference in request duration can be leveraged by actors to enumerate valid names of managed users. LDAP and OpenID Connect users are not affected. The issue has been fixed in Dependency-Track 4.12.2.

An issue was discovered in Kurmi Provisioning Suite before 7.9.0.35, 7.10.x through 7.10.0.18, and 7.11.x through 7.11.0.15. An Observable Response Discrepancy vulnerability in the sendPasswordReinitLink action of the unlogged.do page allows remote attackers to test whether a username is valid or not. This allows confirmation of valid usernames.

Accounts enumeration vulnerability in the Login Component of Reolink Duo 2 WiFi Camera (Firmware Version v3.0.0.1889_23031701) allows remote attackers to determine valid user accounts via login attempts. This can lead to the enumeration of user accounts and potentially facilitate other attacks, such as brute-forcing of passwords. The vulnerability arises from the application responding differently to login attempts with valid and invalid usernames.

Zabbix through 4.4.0alpha1 allows User Enumeration. With login requests, it is possible to enumerate application usernames based on the variability of server responses (e.g., the "Login name or password is incorrect" and "No permissions for system access" messages, or just blocking for a number of seconds). This affects both api_jsonrpc.php and index.php.

Zitadel is an open source identity management system. 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". Due to a implementation change to prevent deadlocks calling the database, the flag would not be correctly respected in all cases and an attacker would gain information if an account exist within ZITADEL, since the error message shows "object not found" instead of the generic error message. This vulnerability is fixed in 2.58.1, 2.57.1, 2.56.2, 2.55.5, 2.54.8, and 2.53.9.

In veilid-core in Veilid before 0.3.4, the protocol's ping function can be misused in a way that decreases the effectiveness of safety and private routes.

IBM TXSeries for Multiplatforms 10.1 could allow an attacker to determine valid usernames due to an observable timing discrepancy which could be used in further attacks against the system.

In NocoDB, versions 0.9 to 0.83.8 are vulnerable to Observable Discrepancy in the password-reset feature. When requesting a password reset for a given email address, the application displays an error message when the email isn't registered within the system. This allows attackers to enumerate the registered users' email addresses.

A vulnerability in the TLS handler of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to gain access to sensitive information. This vulnerability is due to improper implementation of countermeasures against a Bleichenbacher attack on a device that uses SSL decryption policies. An attacker could exploit this vulnerability by sending crafted TLS messages to an affected device, which would act as an oracle and allow the attacker to carry out a chosen-ciphertext attack. A successful exploit could allow the attacker to perform cryptanalytic operations that may allow decryption of previously captured TLS sessions to the affected device.

A vulnerability in Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), and Cisco Unity Connection could allow an unauthenticated, remote attacker to perform a timing attack. This vulnerability is due to insufficient protection of a system password. An attacker could exploit this vulnerability by observing the time it takes the system to respond to various queries. A successful exploit could allow the attacker to determine a sensitive system password.

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.

Observable discrepancies in the login process allow an attacker to guess legitimate user names registered in the BMC. This issue affects: Lanner Inc IAC-AST2500A standard firmware version 1.10.0.