CVE-2018-11778

Vulnerability

Apache Ranger versions prior to 1.2.0 contain a stack-based buffer overflow vulnerability in the UnixAuthenticationService component. The service fails to properly validate user input, allowing an attacker to overflow a stack buffer. This affects all deployments using the Unix authentication service [1][2][3][4].

Exploitation

An attacker with network access to the Apache Ranger service can send a specially crafted request to the UnixAuthenticationService endpoint. No authentication is required to trigger the overflow. The crafted input causes the service to write beyond the bounds of a stack-allocated buffer, potentially overwriting critical control data [3][4].

Impact

Successful exploitation of this buffer overflow can lead to arbitrary code execution in the context of the Ranger service process. This could allow the attacker to compromise the Ranger server, access sensitive policy data, or pivot to other systems. The vulnerability is rated Critical (CVSS 9.8) [3][4].

Mitigation

Users should upgrade to Apache Ranger 1.2.0 or later, which includes the fix that properly validates user input in UnixAuthenticationService [1][2][3][4]. No workarounds are available for versions prior to 1.2.0.