Source: cve@mitre.org
REDCap 14.3.13 allows an attacker to enumerate usernames due to an observable discrepancy between login attempts.
REDCap 14.3.13 is vulnerable to username enumeration, allowing attackers to identify valid user accounts. This vulnerability leverages a timing discrepancy in login attempt responses, enabling attackers to systematically probe for valid usernames and subsequently launch further attacks. Successful exploitation can lead to account compromise and potential data breaches.
Step 1: Initial Probe: The attacker sends a login request with a known or guessed username and password to the REDCap login endpoint.
Step 2: Response Analysis: The attacker observes the response from the server. This could involve analyzing response times, error messages, or HTTP status codes.
Step 3: Username Iteration: The attacker iterates through a list of potential usernames, sending login requests for each.
Step 4: Differentiation: The attacker compares the responses received for each username. Valid usernames will exhibit a different response (e.g., slightly longer response time, different error message) compared to invalid usernames.
Step 5: Username Identification: The attacker identifies valid usernames based on the observed discrepancies.
Step 6: Further Exploitation (Optional): Once valid usernames are identified, the attacker can attempt password guessing, brute-force attacks, or other attacks targeting those accounts.
The vulnerability stems from an inconsistent response time or error message differentiation between valid and invalid username attempts. Specifically, the application likely provides slightly different feedback (e.g., response time, error message) depending on whether the entered username exists in the system. An attacker can leverage this observable difference to systematically probe the system with various usernames. The root cause is a lack of proper rate limiting or consistent error handling for login attempts, allowing attackers to differentiate between valid and invalid usernames. This flaw doesn't directly involve a buffer overflow or SQL injection, but rather a timing-based side-channel attack. The application's design fails to adequately obscure the presence or absence of a user account, making it susceptible to enumeration.
Due to the ease of exploitation and potential for widespread impact, this vulnerability poses a threat to any organization using REDCap 14.3.13. No specific APT groups are currently linked, but the vulnerability's nature makes it attractive to a wide range of attackers, including those seeking initial access. CISA KEV status: Not Listed.
Monitor web server logs for a high volume of failed login attempts from a single IP address or user agent, especially if the attempts target a known REDCap login endpoint.
Analyze network traffic for patterns of login requests with varying response times or error messages. Tools like Wireshark can be used to capture and analyze HTTP traffic.
Implement intrusion detection systems (IDS) with rules to detect suspicious login activity, such as rapid login attempts or attempts with a large number of invalid usernames.
Monitor for changes in the application's behavior, such as differences in response times or error messages, that could indicate an enumeration attempt.
Upgrade to a patched version of REDCap that addresses the vulnerability. Consult the vendor's security advisories for specific patch details.
Implement rate limiting on login attempts to prevent brute-force attacks and slow down enumeration attempts. Limit the number of login attempts from a single IP address or user account within a specific timeframe.
Ensure consistent error messages and response times for all login attempts, regardless of whether the username is valid or invalid. This prevents attackers from differentiating between valid and invalid usernames.
Implement account lockout policies after a certain number of failed login attempts. This can prevent attackers from brute-forcing passwords.
Use multi-factor authentication (MFA) to add an extra layer of security to user accounts.
Regularly review and update security configurations and best practices for the web server and application.