CVE-2023-34042 identifies a security vulnerability in the Spring Security framework, specifically related to the spring-security.xsd file contained within the spring-security-config jar. The vulnerability arises because this XML Schema Definition (XSD) file is assigned world-writable permissions when extracted, meaning any user with access to the file system can modify it. This is categorized under CWE-732: Incorrect Permission Assignment for Critical Resource. Although no active exploits have been reported in the wild, the improper permission setting poses a risk because an attacker with local access could alter the XSD file, potentially influencing how Spring Security configurations are validated or interpreted. This could lead to unauthorized privilege escalation or other integrity violations within applications relying on Spring Security for authentication and authorization. The affected versions include Spring Security 6.1.x prior to 6.1.4, 6.0.x prior to 6.0.7, 5.8.x prior to 5.8.7, and 5.7.x prior to 5.7.11. The CVSS 3.1 base score is 4.1 (medium severity), reflecting that exploitation requires local access with high privileges and no user interaction, impacting integrity but not confidentiality or availability. The vulnerability does not directly expose data but compromises the integrity of a critical security configuration resource, which could be leveraged in complex attack chains. Users are advised to update to the latest patched versions of Spring Security to remediate this issue and prevent potential future exploits that might leverage this permission misconfiguration.

For European organizations, the impact of this vulnerability depends largely on the deployment context of Spring Security. Many enterprises and public sector entities across Europe use Spring Security to protect web applications and APIs. If an attacker gains local access to a system hosting a vulnerable Spring Security version, they could modify the spring-security.xsd file, potentially undermining security policies and enabling privilege escalation or bypass of security controls. This could lead to unauthorized access to sensitive data or critical systems, especially in sectors like finance, healthcare, and government where Spring-based applications are common. Although exploitation requires local privileged access, insider threats or attackers who have already compromised a low-privilege account could escalate their privileges. The integrity compromise could also undermine trust in application security, leading to compliance issues under GDPR and other European data protection regulations. The absence of known exploits reduces immediate risk, but the vulnerability represents a latent threat that could be weaponized in targeted attacks against high-value European organizations.

To mitigate this vulnerability, European organizations should: 1) Immediately upgrade Spring Security to the latest patched versions (6.1.4 or later, 6.0.7 or later, 5.8.7 or later, or 5.7.11 or later) where the permission issue is resolved. 2) Audit file system permissions on all Spring Security-related files, especially spring-security.xsd, ensuring they are not world-writable and adhere to the principle of least privilege. 3) Implement strict access controls and monitoring on servers running Spring Security to detect unauthorized file modifications, using file integrity monitoring tools. 4) Restrict local access to application servers to trusted administrators only, minimizing the risk of local privilege abuse. 5) Incorporate this vulnerability into vulnerability management and patching workflows to ensure timely updates. 6) Conduct security reviews of application deployment environments to verify no other critical resources have insecure permissions. 7) Educate development and operations teams about the risks of improper file permissions and secure configuration management practices. These steps go beyond generic advice by focusing on permission audits, access restrictions, and proactive monitoring tailored to the nature of this vulnerability.