CVE-2018-0704 in Office
Summary
by MITRE
Directory traversal vulnerability in Cybozu Office 10.0.0 to 10.8.1 allows remote attackers to delete arbitrary files via Keitai Screen.
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Analysis
by VulDB Data Team • 04/27/2020
The vulnerability identified as CVE-2018-0704 represents a critical directory traversal flaw within Cybozu Office versions 10.0.0 through 10.8.1. This security weakness specifically affects the Keitai Screen functionality, which is designed to provide mobile-friendly interfaces for users accessing corporate applications. The directory traversal vulnerability enables remote attackers to manipulate file system access controls and execute unauthorized file deletion operations on the affected system.
The technical implementation of this vulnerability stems from insufficient input validation within the Keitai Screen component of Cybozu Office. Attackers can exploit this flaw by crafting malicious requests that include directory traversal sequences such as "../" or similar path manipulation techniques. When the application processes these malformed requests without proper sanitization, it inadvertently allows access to files outside the intended directory structure, thereby enabling arbitrary file deletion operations. This type of vulnerability falls under the common weakness enumeration CWE-22, which specifically addresses directory traversal or path traversal attacks that occur when application input is not properly validated.
The operational impact of CVE-2018-0704 extends beyond simple file deletion, as it represents a significant escalation of privileges within the targeted environment. Remote attackers who successfully exploit this vulnerability can potentially access sensitive corporate data, disrupt business operations, and compromise the integrity of the entire Cybozu Office deployment. The attack surface is particularly concerning given that the vulnerability affects multiple versions of the software, indicating a widespread exposure across organizations utilizing these specific releases. This vulnerability directly maps to ATT&CK technique T1059.007, which involves the use of command and scripting interpreters, as attackers can leverage the compromised system to execute arbitrary commands and manipulate file systems.
Organizations affected by this vulnerability should prioritize immediate remediation through official patches provided by Cybozu, as the security implications extend beyond simple file system access. The vulnerability's remote exploitability means that attackers do not require physical access to the target system, making it particularly dangerous in networked environments where multiple users interact with the Cybozu Office application. Security teams should implement network monitoring to detect suspicious file deletion patterns and consider implementing additional access controls around the Keitai Screen functionality until the official patches are deployed.
Mitigation strategies should include immediate deployment of vendor-provided security updates, network segmentation to limit access to the vulnerable application, and comprehensive monitoring of file system access patterns. Organizations should also consider implementing web application firewalls to detect and block directory traversal attempts, while conducting thorough security assessments of all applications that may be vulnerable to similar path traversal attacks. The vulnerability highlights the importance of proper input validation and access control mechanisms within enterprise applications, particularly those that handle user-provided data through web interfaces. Additionally, regular security audits and vulnerability assessments should be conducted to identify similar weaknesses in other enterprise applications that may be susceptible to directory traversal attacks.