CVE-2025-22233 in Spring Framework
Summary
by MITRE • 05/16/2025
CVE-2024-38820 ensured Locale-independent, lowercase conversion for both the configured disallowedFields patterns and for request parameter names. However, there are still cases where it is possible to bypass the disallowedFields checks.
Affected Spring Products and Versions
Spring Framework: * 6.2.0 - 6.2.6
* 6.1.0 - 6.1.19
* 6.0.0 - 6.0.27
* 5.3.0 - 5.3.42 * Older, unsupported versions are also affected
Mitigation
Users of affected versions should upgrade to the corresponding fixed version.
Affected version(s)Fix Version Availability 6.2.x 6.2.7 OSS6.1.x 6.1.20 OSS6.0.x 6.0.28 Commercial https://enterprise.spring.io/ 5.3.x 5.3.43 Commercial https://enterprise.spring.io/ No further mitigation steps are necessary.
Generally, we recommend using a dedicated model object with properties only for data binding, or using constructor binding since constructor arguments explicitly declare what to bind together with turning off setter binding through the declarativeBinding flag. See the Model Design section in the reference documentation.
For setting binding, prefer the use of allowedFields (an explicit list) over disallowedFields.
Credit
This issue was responsibly reported by the TERASOLUNA Framework Development Team from NTT DATA Group Corporation.
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Analysis
by VulDB Data Team • 05/23/2025
The vulnerability identified as CVE-2025-22233 represents a critical bypass opportunity within Spring Framework's data binding mechanisms, specifically affecting the disallowedFields validation process. This issue stems from incomplete implementation of locale-independent lowercase conversion that was previously addressed in CVE-2024-38820, leaving gaps in the security controls designed to prevent unauthorized field access during request parameter binding. The flaw manifests in Spring Framework versions ranging from 5.3.0 through 6.2.6, with older unsupported versions also being vulnerable, creating a substantial attack surface across multiple major releases.
The technical implementation of this vulnerability exploits the inconsistency in how field name comparisons are handled during data binding operations. While the framework correctly applies lowercase conversion to configured disallowedFields patterns and request parameter names, certain edge cases and specific parameter name formats can circumvent these checks. This bypass occurs when the validation logic fails to properly normalize parameter names in all scenarios, allowing malicious actors to inject parameters that should be blocked by disallowedFields configurations. The vulnerability operates at the application layer and can be categorized under CWE-284 Access Control, specifically related to improper field validation during data binding operations.
Operationally, this vulnerability presents significant risk to applications relying on Spring Framework's data binding features, particularly those that depend on disallowedFields for security enforcement. Attackers could potentially manipulate request parameters to access or modify fields that should remain protected, leading to unauthorized data access, modification, or even privilege escalation depending on the application's architecture. The impact extends beyond simple data exposure, as successful exploitation could enable attackers to bypass security controls designed to prevent access to internal application components or sensitive data fields.
The recommended mitigation strategy involves upgrading to the fixed versions as specified in the advisory, with particular attention to the version numbers provided for each release line. Organizations should prioritize upgrading their Spring Framework installations to versions 6.2.7, 6.1.20, 6.0.28, and 5.3.43 respectively. Beyond the immediate upgrade, security architects should consider implementing more robust data binding practices including the use of dedicated model objects with explicit property declarations rather than relying on automatic binding mechanisms. The ATT&CK framework's T1210 Exploitation of Remote Services and T1078 Valid Accounts categories are relevant here, as this vulnerability could enable attackers to gain unauthorized access to application functionality through manipulated parameter binding.
Additional security measures should include implementing allowedFields configurations instead of relying on disallowedFields, as explicit allowlists provide stronger security boundaries than blacklists. The reference documentation's recommendations regarding model design and constructor binding should be implemented, particularly the use of declarativeBinding flag to disable setter-based binding. Organizations should also consider implementing comprehensive input validation at multiple layers of their applications, including API gateways and front-end validation, to create defense-in-depth controls. The vulnerability's nature makes it particularly dangerous in environments where Spring Framework's data binding is used extensively for REST API endpoints, as attackers could potentially exploit this to manipulate application state or access restricted data through carefully crafted parameter names.