CVE-2025-37734 is a vulnerability identified in Elastic Kibana, specifically affecting versions 8.12.0, 9.1.0, and 9.2.0. The root cause is an origin validation error classified under CWE-346, where the application fails to properly validate the Origin HTTP header. This flaw is exploited via the Observability AI Assistant component, which processes incoming requests and their headers. An attacker with low privileges can craft a malicious Origin header to trigger Server-Side Request Forgery (SSRF), causing the Kibana server to make unintended HTTP requests to internal or external systems. SSRF can be leveraged to scan internal networks, access internal services not exposed externally, or potentially exploit other vulnerabilities in internal systems. The vulnerability does not require user interaction and does not directly compromise confidentiality or availability but can affect the integrity of internal network operations. The CVSS 3.1 base score is 4.3, indicating medium severity, with attack vector as network, low attack complexity, requiring privileges but no user interaction. No patches are currently linked, and no known exploits have been reported in the wild as of the published date. The vulnerability was reserved in April 2025 and published in November 2025.

For European organizations, the impact of CVE-2025-37734 can be significant in environments where Kibana is used extensively for observability, monitoring, and analytics, especially in critical infrastructure sectors such as finance, energy, and telecommunications. SSRF can allow attackers to pivot from the Kibana server into internal networks, potentially accessing sensitive internal services or data not otherwise exposed. This could lead to further exploitation, data integrity issues, or lateral movement within the network. Although the vulnerability does not directly expose confidential data or cause service outages, the indirect risks through SSRF can be substantial, particularly in tightly regulated environments with strict data protection requirements such as GDPR. The medium severity rating reflects that while the immediate impact is limited, the potential for chained attacks or reconnaissance is a concern. Organizations relying on Kibana’s Observability AI Assistant feature should be particularly vigilant.

1. Monitor Elastic’s official channels for patches addressing CVE-2025-37734 and apply them promptly once available. 2. Until patches are released, restrict network egress from Kibana servers to only necessary destinations to limit SSRF exploitation scope. 3. Implement strict validation and filtering of HTTP Origin headers at the application or proxy level to prevent forged headers from reaching Kibana. 4. Employ network segmentation to isolate Kibana servers from sensitive internal services to reduce the impact of potential SSRF attacks. 5. Conduct regular security audits and penetration tests focusing on SSRF and header validation weaknesses in observability tools. 6. Review and harden Kibana user privileges to minimize the number of users with the required privileges to exploit this vulnerability. 7. Enable detailed logging and monitoring of unusual outbound requests from Kibana servers to detect potential exploitation attempts early.