CVE-2018-11409 in Splunk
Summary
by MITRE
Splunk through 7.0.1 allows information disclosure by appending __raw/services/server/info/server-info?output_mode=json to a query, as demonstrated by discovering a license key.
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Analysis
by VulDB Data Team • 12/24/2024
The vulnerability identified as CVE-2018-11409 affects Splunk versions through 7.0.1 and represents a critical information disclosure flaw that enables unauthorized access to sensitive system information. This vulnerability arises from insufficient access controls within Splunk's web interface, specifically in the server information endpoint that exposes administrative details without proper authentication verification. The flaw allows an attacker to construct a malicious query by appending __raw/services/server/info/server-info?output_mode=json to any valid Splunk URL, thereby bypassing normal authorization mechanisms and gaining access to server configuration data that should remain protected. The vulnerability directly impacts the principle of least privilege and demonstrates a failure in Splunk's input validation and access control implementation.
The technical exploitation of this vulnerability occurs through the manipulation of Splunk's REST API endpoints, specifically targeting the server-info service which contains sensitive administrative information including license keys, server configuration details, and potentially other system-level data. This flaw operates under CWE-200, which classifies information exposure vulnerabilities, and represents a clear violation of the principle that sensitive system information should only be accessible to authorized administrative users. The vulnerability's impact extends beyond simple license key disclosure, as the server-info endpoint typically contains additional configuration parameters that could aid in further exploitation attempts. The issue manifests as a lack of proper authentication checks within the web framework's request handling mechanism, allowing unauthenticated access to administrative endpoints.
From an operational standpoint, this vulnerability creates significant risk for organizations using affected Splunk versions, as license key disclosure can lead to unauthorized access to enterprise security monitoring capabilities and potentially enable attackers to bypass license restrictions or gain insights into the organization's security infrastructure. The vulnerability's impact aligns with ATT&CK technique T1083, which covers discovering system information, and T1005, which addresses data from local system. Organizations may face compliance violations and security breaches when license keys are exposed, as these keys often contain critical licensing information that could be exploited for unauthorized system access or to gain additional privileges within the Splunk environment. The exposure of such information could facilitate more sophisticated attacks targeting the Splunk infrastructure itself.
Organizations should immediately implement mitigations including updating to Splunk versions 7.0.2 or later where this vulnerability has been addressed through proper access control enforcement. Network segmentation and firewall rules should be implemented to restrict access to Splunk's administrative endpoints, particularly those handling sensitive server information. Additionally, organizations should conduct comprehensive audits of their Splunk configurations to ensure that unnecessary administrative endpoints are not exposed to untrusted networks. The remediation process should include disabling unnecessary services, implementing proper authentication mechanisms, and establishing monitoring for suspicious access patterns to Splunk administrative interfaces. Regular security assessments and penetration testing should be conducted to verify that access controls remain effective against similar information disclosure vulnerabilities.