CVE-2024-48944 is a Server-Side Request Forgery (SSRF) vulnerability identified in Apache Kylin versions 5.0.0 through 5.0.1. Apache Kylin is an open-source distributed analytics engine designed to provide SQL interface and multi-dimensional analysis (OLAP) on Hadoop and other big data platforms. The vulnerability arises when an attacker with administrative access to a Kylin server exploits the ability to forge HTTP requests targeting the internal network. Specifically, the attacker can invoke the "/kylin/api/xxx/diag" API endpoint on other internal hosts accessible from the compromised Kylin server. This API endpoint, if exposed on internal hosts, may leak sensitive diagnostic information. The SSRF attack vector allows the attacker to bypass network restrictions and access internal services that are not directly exposed externally. The preconditions for exploitation are significant: the attacker must already have admin privileges on the Kylin server, and there must be other internal hosts running the vulnerable diagnostic API endpoint. The vulnerability does not require user interaction and can be exploited remotely over the network. The CVSS v3.1 base score is 6.5 (medium severity), reflecting the network attack vector, low attack complexity, requirement for privileges, no user interaction, and high impact on confidentiality but no impact on integrity or availability. The issue was addressed in Apache Kylin version 5.0.2, which users are strongly advised to upgrade to in order to remediate this vulnerability. No known exploits are currently reported in the wild, but the potential for sensitive information disclosure within internal networks poses a risk to organizations using affected versions of Apache Kylin.

For European organizations, the impact of CVE-2024-48944 can be significant in environments where Apache Kylin is deployed for big data analytics, especially in sectors handling sensitive or regulated data such as finance, healthcare, telecommunications, and government. An attacker with admin access to a Kylin server could leverage this SSRF vulnerability to pivot within the internal network, accessing diagnostic endpoints on other internal systems that may reveal sensitive configuration details, internal IP addresses, or other confidential information. This could facilitate further lateral movement, reconnaissance, or targeted attacks within the organization's infrastructure. The confidentiality breach could lead to compliance violations under GDPR if personal or sensitive data is exposed. Although the vulnerability does not directly affect data integrity or availability, the information disclosure risk can undermine trust and lead to secondary attacks. Given the medium severity and the prerequisite of admin access, the threat is more relevant in scenarios where internal access controls are weak or where insider threats exist. Organizations relying on Apache Kylin for critical analytics workloads should prioritize remediation to prevent potential exploitation that could compromise internal network security.

1. Immediate Upgrade: Upgrade all Apache Kylin instances to version 5.0.2 or later, where the vulnerability is patched. 2. Access Controls: Restrict administrative access to Kylin servers strictly to trusted personnel and enforce strong authentication mechanisms such as multi-factor authentication (MFA). 3. Network Segmentation: Isolate Kylin servers and internal hosts exposing the "/kylin/api/xxx/diag" endpoint within segmented network zones with strict firewall rules to limit lateral movement. 4. API Exposure Review: Audit internal hosts to identify and secure or disable unnecessary diagnostic API endpoints that could be targeted via SSRF. 5. Monitoring and Logging: Implement enhanced monitoring on Kylin servers and internal hosts to detect unusual API request patterns indicative of SSRF attempts or lateral movement. 6. Incident Response Preparedness: Develop and test incident response plans that include scenarios involving SSRF exploitation and internal reconnaissance. 7. Least Privilege Principle: Ensure that Kylin admin accounts have only the necessary privileges and regularly review permissions to minimize risk exposure. 8. Vulnerability Scanning: Regularly scan Kylin deployments and internal services for known vulnerabilities and misconfigurations to proactively identify risks.