CVE-2019-16174 in LimeSurvey
Summary
by MITRE
An XML injection vulnerability was found in Limesurvey before 3.17.14 that allows remote attackers to import specially crafted XML files and execute code or compromise data integrity.
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Analysis
by VulDB Data Team • 12/18/2023
The XML injection vulnerability identified as CVE-2019-16174 affects Limesurvey versions prior to 3.17.14 and represents a critical security flaw that enables remote attackers to manipulate the survey import functionality through maliciously crafted XML files. This vulnerability resides in the application's XML parsing mechanism within the survey import feature, where insufficient input validation and sanitization allows attackers to inject malicious XML content that can be executed within the application context. The flaw essentially permits an attacker to bypass normal security controls and execute arbitrary code on the target system or compromise data integrity during the import process.
The technical implementation of this vulnerability stems from improper handling of XML data during the import operation, where the application fails to properly sanitize or validate XML input before processing. When users attempt to import survey data through XML files, the application's XML parser does not adequately filter or escape special characters that could be interpreted as executable code or malicious commands. This weakness creates a pathway for attackers to inject XML elements that can trigger unintended behavior within the application's processing engine, potentially leading to code execution or data manipulation. The vulnerability is classified under CWE-94 as "Improper Control of Generation of Code ('Code Injection')" and aligns with ATT&CK technique T1059.007 for "Command and Scripting Interpreter: PowerShell" and T1566.001 for "Phishing: Spearphishing Attachment" when attackers leverage this vulnerability to deliver malicious payloads through compromised XML files.
The operational impact of this vulnerability extends beyond simple code execution to encompass potential data compromise and system integrity violations. Attackers could exploit this flaw to gain unauthorized access to survey data, manipulate existing surveys, or potentially escalate privileges within the application environment. The remote nature of the attack means that an attacker does not require physical access to the system or network, making the vulnerability particularly dangerous in environments where multiple users can upload survey files or where automated import processes exist. Additionally, the vulnerability could be exploited as part of a broader attack chain, potentially serving as an initial compromise vector that leads to further system exploitation. Organizations using vulnerable versions of Limesurvey face risks of data breaches, survey manipulation, and potential full system compromise, with the attack surface expanding to include any user with import privileges.
Mitigation strategies for CVE-2019-16174 primarily focus on immediate remediation through version updates to Limesurvey 3.17.14 or later, which includes proper input validation and XML sanitization measures. Organizations should implement additional defensive controls such as restricting XML file upload permissions, implementing strict file type validation, and establishing network segmentation to limit potential attack impact. Security configurations should enforce proper XML parsing with strict validation rules and disable unnecessary XML features that could be exploited. Regular security assessments and penetration testing should be conducted to identify similar vulnerabilities in other applications, while monitoring systems should be configured to detect unusual import activities or file modifications. The vulnerability serves as a reminder of the critical importance of input validation in web applications and aligns with industry best practices outlined in OWASP Top 10 2017 Category A03: Injection, emphasizing the need for proper sanitization of all external inputs before processing.