CVE-2025-63058 is a vulnerability identified in the Hiroaki Miyashita Custom Field Template plugin, affecting all versions up to and including 2.7.4. The issue involves the exposure of sensitive system information to an unauthorized control sphere, meaning that an attacker can retrieve embedded sensitive data from the system through the plugin. The vulnerability requires the attacker to have high privileges (PR:H) and local access (AV:L), with no user interaction needed (UI:N). The CVSS v3.1 score is 4.4, indicating a medium severity level. The vulnerability impacts confidentiality (C:H) but does not affect integrity or availability (I:N/A:N). Since the attacker must already have high-level privileges and local access, this vulnerability primarily facilitates information disclosure rather than remote exploitation. No known exploits are currently in the wild, and no official patches have been linked, suggesting that mitigation relies on access control and monitoring until a patch is released. The vulnerability could be leveraged for further attacks by exposing sensitive configuration or system data embedded within the plugin, which may include credentials, system paths, or other confidential information. The plugin is typically used in content management or customization contexts, and its presence in European organizations depends on adoption rates in various industries.

For European organizations, the primary impact of CVE-2025-63058 is the unauthorized disclosure of sensitive system information, which could facilitate further targeted attacks such as privilege escalation or lateral movement within networks. Since exploitation requires high privileges and local access, the threat is mainly from insider threats or attackers who have already compromised an account with elevated rights. Confidentiality breaches could expose sensitive business data, system configurations, or credentials, potentially leading to data leaks or compliance violations under regulations like GDPR. The vulnerability does not directly affect system integrity or availability, so operational disruption is unlikely. However, the exposure of sensitive information could undermine trust and lead to reputational damage. Organizations in sectors with stringent data protection requirements, such as finance, healthcare, or government, may face increased risks. The lack of known exploits reduces immediate threat levels but does not eliminate the risk of future exploitation once details become widely known.

1. Restrict local high-privilege access strictly to trusted personnel and systems to reduce the attack surface. 2. Implement robust monitoring and logging of access to the Custom Field Template plugin and related system components to detect unusual or unauthorized data retrieval attempts. 3. Conduct regular audits of user privileges to ensure no unnecessary high-level access is granted. 4. Isolate systems running the vulnerable plugin to limit lateral movement opportunities in case of compromise. 5. Once available, promptly apply vendor patches or updates addressing CVE-2025-63058. 6. Use application-layer firewalls or security plugins that can detect and block suspicious plugin behavior. 7. Educate system administrators and users about the risks of privilege misuse and the importance of secure credential management. 8. Consider temporary disabling or replacing the plugin if it is not critical to operations until a patch is released.