webcalendar before 1.2.7 shows the reason for a failed login (e.g., "no such user").

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 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.

A vulnerability in Cisco SD-WAN vManage Software could allow an unauthenticated, remote attacker to enumerate user accounts. This vulnerability is due to the improper handling of HTTP headers. An attacker could exploit this vulnerability by sending authenticated requests to an affected system. A successful exploit could allow the attacker to compare the HTTP responses that are returned by the affected system to determine which accounts are valid user accounts.

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. The ability to enumerate users was possible without relevant permissions due to different handling depending on whether the user existed or not when attempting to use the switch users functionality. We now ensure that 403s are returned whether the user exists or not if a user cannot switch to a user or if the user does not exist. The patch for this issue is available for branch 3.4.

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.

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.

LabVantage LIMS 8.3 does not properly maintain the confidentiality of database names. For example, the web application exposes the database name. An attacker might be able to enumerate database names by providing his own database name in a request, because the response will return an 'Unrecognized Database exception message if the database does not exist.

Kanboard is project management software that focuses on the Kanban methodology. Prior to version 1.2.46, Kanboard is vulnerable to username enumeration and IP spoofing-based brute-force protection bypass. By analyzing login behavior and abusing trusted HTTP headers, an attacker can determine valid usernames and circumvent rate-limiting or blocking mechanisms. Any organization running a publicly accessible Kanboard instance is affected, especially if relying on IP-based protections like Fail2Ban or CAPTCHA for login rate-limiting. Attackers with access to the login page can exploit this flaw to enumerate valid usernames and bypass IP-based blocking mechanisms, putting all user accounts at higher risk of brute-force or credential stuffing attacks. Version 1.2.46 contains a patch for the issue.

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.

_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 MediaWiki before 1.35.1. Missing users (accounts that don't exist) and hidden users (accounts that have been explicitly hidden due to being abusive, or similar) that the viewer cannot see are handled differently, exposing sensitive information about the hidden status to unprivileged viewers. This exists on various code paths.

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.

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.

An email address enumeration vulnerability exists in the password reset function of Rocket.Chat through 3.9.1.

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

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.

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.

Observable Response Discrepancy vulnerability in Tridium Niagara Framework on Windows, Linux, QNX, Tridium Niagara Enterprise Security on Windows, Linux, QNX allows Cryptanalysis. This issue affects Niagara Framework: before 4.14.2, before 4.15.1, before 4.10.11; Niagara Enterprise Security: before 4.14.2, before 4.15.1, before 4.10.11.Tridium recommends upgrading to Niagara Framework and Enterprise Security versions 4.14.2u2, 4.15.u1, or 4.10u.11.

In CentOS-WebPanel.com (aka CWP) CentOS Web Panel 0.9.8.848, the Login process allows attackers to check whether a username is valid by comparing response times.

Dalmark Systems Systeam 2.22.8 build 1724 is vulnerable to User enumeration. The Systeam application is an ERP system that uses a mixed architecture based on SaaS tenant and user management, and on-premise database and web application counterparts. This issue occurs during the password recovery procedure for a given user, where a difference in messages could allow an attacker to determine if the given user is valid or not, enabling a brute force attack with valid users.

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.

IBM Aspera Orchestrator 4.0.1 could allow a remote attacker to enumerate usernames due to observable response discrepancies. IBM X-Force ID: 248545.

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

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.

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.

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.

The authentication method in Laravel 8.x through 9.x before 9.32.0 was discovered to be vulnerable to user enumeration via timeless timing attacks with HTTP/2 multiplexing. This is caused by the early return inside the hasValidCredentials method in the Illuminate\Auth\SessionGuard class when a user is found to not exist.

Meow hash 0.5/calico does not sufficiently thwart key recovery by an attacker who can query whether there's a collision in the bottom bits of the hashes of two messages, as demonstrated by an attack against a long-running web service that allows the attacker to infer collisions by measuring timing differences.

OpenSearch Security is a plugin for OpenSearch that offers encryption, authentication and authorization. There is an observable discrepancy in the authentication response time between calls where the user provided exists and calls where it does not. This issue only affects calls using the internal basic identity provider (IdP), and not other externally configured IdPs. Patches were released in versions 1.3.9 and 2.6.0, there are no workarounds.

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.

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.

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.

Jenkins GitHub Plugin 1.34.4 and earlier uses a non-constant time comparison function when checking whether the provided and computed webhook signatures are equal, allowing attackers to use statistical methods to obtain a valid webhook signature.

TYPO3 is an open source PHP based web content management system released under the GNU GPL. It has been discovered that observing response time during user authentication (backend and frontend) can be used to distinguish between existing and non-existing user accounts. Extension authors of 3rd party TYPO3 extensions providing a custom authentication service should check if the extension is affected by the described problem. Affected extensions must implement new `MimicServiceInterface::mimicAuthUser`, which simulates corresponding times regular processing would usually take. Update to TYPO3 version 7.6.58 ELTS, 8.7.48 ELTS, 9.5.37 ELTS, 10.4.32 or 11.5.16 that fix this problem. There are no known workarounds for this issue.

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

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

Observable Discrepancy in GitHub repository healthchecks/healthchecks prior to v2.6.

A vulnerability has been identified in Desigo DXR2 (All versions < V01.21.142.5-22), Desigo PXC3 (All versions < V01.21.142.4-18), Desigo PXC4 (All versions < V02.20.142.10-10884), Desigo PXC5 (All versions < V02.20.142.10-10884). The login functionality of the application fails to normalize the response times of login attempts performed with wrong usernames with the ones executed with correct usernames. A remote unauthenticated attacker could exploit this side-channel information to perform a username enumeration attack and identify valid 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.

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

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.

Snipe-IT through 6.0.14 allows attackers to check whether a user account exists because of response variations in a /password/reset request.

Jenkins GitLab Plugin 1.5.35 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.

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.

An issue was discovered in MediaWiki before 1.35.8, 1.36.x and 1.37.x before 1.37.5, and 1.38.x before 1.38.3. HTMLUserTextField exposes the existence of hidden users.

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.

OpenCRX before v5.2.2 was discovered to be vulnerable to password enumeration due to the difference in error messages received during a password reset which could enable an attacker to determine if a username, email or ID is valid.

Matrix Tafnit v8 - CWE-204: Observable Response Discrepancy