CVE-2025-5878 is a vulnerability identified in the ESAPI esapi-java-legacy library, specifically within the Encoder.encodeForSQL interface designed to defend against SQL injection attacks. The flaw arises from improper neutralization of special elements, which means that malicious input containing SQL control characters or commands may not be correctly sanitized, allowing attackers to craft SQL injection payloads. This vulnerability affects a wide range of legacy versions from 2.0-rc10 through 2.6.2.0. The issue can be exploited remotely without any authentication or user interaction, increasing its risk profile. The ESAPI project responded promptly by disabling the vulnerable feature by default in version 2.7.0.0 and updating Java class documentation to warn developers about the risks of using encodeForSQL. The CVSS 4.0 base score is 6.9 (medium severity), reflecting network attack vector, low complexity, no privileges or user interaction required, and limited impact on confidentiality, integrity, and availability. While no known exploits are currently active in the wild, the public disclosure means attackers could develop exploits. The vulnerability primarily threatens applications relying on ESAPI for SQL injection defense, potentially leading to unauthorized data access, data manipulation, or database compromise if exploited. The mitigation involves upgrading to ESAPI 2.7.0.0 or later, disabling or avoiding the use of encodeForSQL, and reviewing application code for unsafe encoding practices. Additionally, developers should heed updated documentation warnings and consider alternative, more robust SQL injection prevention methods such as parameterized queries or ORM frameworks.

For European organizations, the impact of CVE-2025-5878 can be significant, particularly for those relying on legacy Java applications that utilize the ESAPI esapi-java-legacy library for input validation and SQL injection defense. Exploitation could lead to unauthorized access to sensitive data, data corruption, or disruption of critical business processes. This is especially critical for sectors like finance, healthcare, government, and critical infrastructure where data integrity and confidentiality are paramount. Given the vulnerability allows remote exploitation without authentication or user interaction, attackers could automate attacks at scale, increasing risk. The medium severity rating indicates a moderate but tangible risk, with potential for data breaches or compliance violations under GDPR if personal data is exposed. Organizations with legacy systems that have not been updated to ESAPI 2.7.0.0 or later are particularly vulnerable. The vulnerability also poses reputational risks and potential financial losses due to remediation costs and regulatory penalties.

1. Upgrade all ESAPI esapi-java-legacy library instances to version 2.7.0.0 or later immediately, as this version disables the vulnerable encodeForSQL feature by default and includes warnings in documentation. 2. Conduct a thorough code audit to identify and refactor any usage of Encoder.encodeForSQL, replacing it with safer alternatives such as parameterized SQL queries or prepared statements. 3. Implement runtime application self-protection (RASP) or web application firewalls (WAF) with SQL injection detection rules as an additional layer of defense. 4. Educate developers about the risks associated with improper encoding and the importance of following secure coding guidelines, especially when handling database inputs. 5. Monitor application logs and network traffic for unusual SQL query patterns or injection attempts. 6. Establish a patch management process to ensure timely updates of third-party libraries and dependencies. 7. Review and update security policies to mandate the use of secure coding practices and regular dependency vulnerability assessments.