CVE-2017-9806 in OpenOffice
Summary
by MITRE
A vulnerability in the OpenOffice Writer DOC file parser before 4.1.4, and specifically in the WW8Fonts Constructor, allows attackers to craft malicious documents that cause denial of service (memory corruption and application crash) potentially resulting in arbitrary code execution.
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Analysis
by VulDB Data Team • 01/24/2021
The vulnerability identified as CVE-2017-9806 represents a critical memory corruption flaw within the OpenOffice Writer application's document parsing capabilities. This issue specifically affects the WW8Fonts Constructor component responsible for handling Microsoft Word 8.0 document formats, which are commonly used for compatibility with legacy office documents. The vulnerability exists in OpenOffice versions prior to 4.1.4, making a substantial portion of the user base susceptible to exploitation. Attackers can craft specially malformed DOC files that trigger buffer overflow conditions when the application attempts to parse these documents, leading to unpredictable memory behavior and system instability.
The technical exploitation of this vulnerability occurs through the manipulation of document structure elements within the WW8Fonts Constructor, which processes font information stored in Word 8.0 format documents. When the parser encounters malformed font data or improperly structured font tables, it fails to properly validate input parameters, resulting in memory corruption that can cause the application to crash or potentially execute arbitrary code. This type of vulnerability falls under the CWE-121 category of stack-based buffer overflow, where insufficient bounds checking allows attackers to overwrite adjacent memory locations. The flaw demonstrates characteristics consistent with heap-based memory corruption issues that can be leveraged for privilege escalation or remote code execution in certain conditions.
The operational impact of CVE-2017-9806 extends beyond simple application instability, as it represents a potential gateway for more sophisticated attacks within enterprise environments. Organizations using OpenOffice Writer for document processing are at risk of experiencing service interruptions, data loss, and potential security breaches when malicious documents are processed. The vulnerability is particularly concerning in email systems, document sharing platforms, and collaborative environments where users may inadvertently open compromised documents. Attackers can leverage this flaw to disrupt business operations through denial of service attacks or to establish persistent access through code execution capabilities, making it a significant concern for IT security teams managing office productivity suites.
Mitigation strategies for this vulnerability should prioritize immediate patching of OpenOffice installations to version 4.1.4 or later, which includes enhanced input validation and memory management protections. Organizations should implement document filtering mechanisms that scan incoming files for suspicious patterns and restrict access to potentially malicious content through sandboxing techniques. Network administrators should consider implementing email security solutions that can detect and block known malicious document formats before they reach end-user systems. The remediation approach aligns with ATT&CK technique T1203 for Exploitation for Client Execution, emphasizing the need for application hardening and input validation controls. Additionally, security awareness training should be implemented to educate users about the risks of opening untrusted documents, while system monitoring should be enhanced to detect unusual application behavior that may indicate exploitation attempts.