CVE-2026-59270 in Security
Summary
by MITRE • 08/27/2026
Spring Security's embedded UnboundID LDAP server (UnboundIdContainer) unconditionally registers an administrative credential and binds its listener to all available network interfaces. Spring Security 7.1.0 Spring Security 7.0.0 - 7.0.6 Spring Security 6.5.0 - 6.5.11 Spring Security 6.4.0 - 6.4.18 Spring Security 5.8.0 - 5.8.27 Spring Security 5.7.0 - 5.7.25
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Analysis
by VulDB Data Team • 08/27/2026
The vulnerability identified in the embedded UnboundID LDAP server, specifically within the UnboundIdContainer implementation of Spring Security, represents a critical misconfiguration that exposes internal authentication mechanisms to unauthorized network access. This issue affects multiple versions of Spring Security, including 7.1.0, ranges from 7.0.0 through 7.0.6, 6.5.0 through 6.5.11, 6.4.0 through 6.4.18, and legacy branches such as 5.8.0 through 5.8.27 and 5.7.0 through 5.7.25. The core of the flaw lies in how the embedded LDAP server is initialized during testing or development phases where this container is typically utilized for integration tests. By default, the configuration binds the LDAP listener to all available network interfaces rather than restricting it to localhost or a specific test interface. This broad binding effectively exposes the administrative credentials and directory services to any host on the local network segment or potentially wider networks depending on firewall rules, creating an unintended attack surface in environments where these tests are executed.
From a technical perspective, this vulnerability is classified under CWE-284 Improper Access Control and CWE-798 Use of Hard-coded Credentials. The administrative credential used by the UnboundIDContainer is registered unconditionally without requiring explicit configuration to restrict its scope or complexity. When combined with the network binding issue, it allows any entity capable of reaching the host's IP address on the LDAP port to authenticate as an administrator. This bypasses standard security boundaries that rely on network segmentation for protection during test execution. The ATT&CK framework maps this behavior to T1078 Valid Accounts and potentially T1526 Cloud Service Discovery if used in cloud-native environments, as it facilitates lateral movement by providing valid administrative credentials over the network without proper access restrictions.
The operational impact of this vulnerability is severe, particularly in continuous integration pipelines or development environments where automated tests run frequently. An attacker with local network access could exploit this to gain full control over the embedded LDAP directory used for testing application security logic. This could lead to data exfiltration if sensitive test data is stored within the directory, privilege escalation by leveraging these credentials against other services that might trust the same authentication source, or disruption of service availability through malicious modifications to the directory structure. In production-like environments where such containers are mistakenly left enabled, the risk escalates significantly as it could expose internal infrastructure details and compromise application security testing integrity.
Mitigation strategies must focus on restricting network exposure and securing credentials by default. Developers should ensure that the UnboundIdContainer is configured to bind only to localhost or 127.0.0.1 when running in environments where external access is not strictly required for test execution. This can often be achieved through specific configuration properties provided by Spring Boot or direct bean customization to set the port and host binding explicitly. Additionally, it is crucial to audit build pipelines and development setups to ensure that embedded LDAP servers are disabled or properly secured before deployment to any environment beyond isolated local testing spaces. Upgrading to patched versions where this behavior may be corrected or better documented with secure defaults is also recommended if available in future releases of Spring Security.