CVE-2019-16180 in LimeSurvey
Summary
by MITRE
Limesurvey before 3.17.14 allows remote attackers to bruteforce the login form and enumerate usernames when the LDAP authentication method is used.
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Analysis
by VulDB Data Team • 12/18/2023
The vulnerability identified as CVE-2019-16180 affects LimeSurvey versions prior to 3.17.14 and represents a critical authentication weakness that specifically impacts systems utilizing LDAP authentication methods. This flaw enables remote attackers to conduct brute force attacks against the login form while simultaneously allowing username enumeration, creating a dangerous combination that significantly undermines the security posture of affected deployments. The vulnerability stems from insufficient input validation and response handling within the authentication module when LDAP integration is active, exposing the system to automated attack vectors that can systematically test credentials and identify valid user accounts.
The technical implementation of this vulnerability manifests through the improper handling of authentication requests in LimeSurvey's LDAP integration component. When LDAP authentication is enabled, the system fails to implement adequate rate limiting or account lockout mechanisms that would normally prevent automated credential testing. Additionally, the application provides distinct response behaviors for valid and invalid usernames, allowing attackers to distinguish between existing and non-existing accounts through timing differences or specific error messages. This username enumeration capability, combined with the lack of protection against rapid successive authentication attempts, creates an ideal environment for credential stuffing and brute force attacks that can systematically compromise user accounts.
The operational impact of CVE-2019-16180 extends beyond immediate credential compromise to encompass broader security implications for organizations relying on LimeSurvey for sensitive data collection and survey management. Attackers exploiting this vulnerability can systematically identify valid user accounts within the system, potentially leading to unauthorized access to survey data, administrative functions, and sensitive information collected through surveys. The vulnerability is particularly dangerous in environments where LimeSurvey is used for collecting confidential information such as medical records, financial data, or personal identifiable information, as the compromised credentials could provide access to substantial amounts of sensitive data. Organizations may also face regulatory compliance issues if survey data is subject to privacy regulations such as gdpr or hipaa.
Mitigation strategies for this vulnerability require immediate implementation of several security controls and system updates. The primary recommendation involves upgrading to LimeSurvey version 3.17.14 or later, which includes patches specifically addressing the authentication handling flaws. Organizations should also implement robust rate limiting mechanisms at the network level to prevent rapid successive authentication attempts, along with account lockout policies that temporarily disable accounts after multiple failed login attempts. Additional protective measures include configuring firewalls to limit access to authentication endpoints, implementing multi-factor authentication to add additional security layers, and conducting regular security audits of authentication systems. This vulnerability aligns with CWE-307, which addresses inadequate account lockout mechanisms, and corresponds to ATT&CK technique T1110.003, which covers credential stuffing attacks, highlighting the importance of implementing proper authentication controls to prevent unauthorized access to sensitive systems and data.