CVE-2012-2149 in OpenOffice
Summary
by MITRE
The WPXContentListener::_closeTableRow function in WPXContentListener.cpp in libwpd 0.8.8, as used by OpenOffice.org (OOo) before 3.4, allows remote attackers to execute arbitrary code via a crafted Wordperfect .WPD document that causes a negative array index to be used. NOTE: some sources report this issue as an integer overflow.
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Analysis
by VulDB Data Team • 03/24/2021
The vulnerability identified as CVE-2012-2149 represents a critical memory corruption flaw affecting the libwpd library version 0.8.8 and its integration within OpenOffice.org before version 3.4. This security weakness resides within the WPXContentListener::_closeTableRow function located in the WPXContentListener.cpp source file, demonstrating how seemingly benign document processing operations can conceal dangerous execution paths. The flaw manifests when processing specially crafted Wordperfect .WPD files that trigger a negative array index condition, creating a scenario where attackers can manipulate memory access patterns to achieve arbitrary code execution. The vulnerability's classification as both a memory corruption issue and an integer overflow highlights the underlying mathematical manipulation that leads to the exploitable state, where standard integer arithmetic fails to properly validate boundary conditions.
The technical exploitation of this vulnerability occurs through careful construction of Wordperfect document structures that force the _closeTableRow function to calculate a negative array index during document parsing operations. When libwpd processes these malformed documents, the negative index calculation results in memory corruption that can be leveraged by attackers to overwrite critical memory locations or redirect program execution flow. This type of vulnerability falls under the CWE-129 weakness category, specifically addressing improper validation of array indices, and aligns with ATT&CK technique T1059.007 for execution through word processors. The flaw demonstrates how buffer overflow conditions can arise from integer underflow scenarios, where mathematical operations produce values that exceed the expected range of valid array indices, creating exploitable memory access patterns.
The operational impact of this vulnerability extends beyond simple code execution capabilities to encompass full system compromise when exploited within the context of document processing applications. OpenOffice.org users operating versions prior to 3.4 face significant risk when opening untrusted Wordperfect documents, as the attack surface includes any application that utilizes the vulnerable libwpd library for document conversion or processing. The vulnerability's remote exploitability means that malicious actors can deliver payloads through email attachments, web downloads, or shared network resources without requiring local system access. Security researchers have documented similar patterns in other office suite vulnerabilities, where document parser flaws create pathways for privilege escalation and persistent system compromise, making this issue particularly concerning for enterprise environments where document processing is common.
Mitigation strategies for CVE-2012-2149 focus primarily on updating affected systems to versions that contain patched implementations of the libwpd library and OpenOffice.org components. System administrators should prioritize immediate deployment of security patches released by Apache Software Foundation and other affected vendors, as these updates contain fixes that properly validate array index calculations and prevent negative values from being used in memory operations. Additional protective measures include implementing document filtering policies that restrict or scan Wordperfect file types, utilizing sandboxing techniques for document processing, and maintaining updated antivirus signatures that can detect malicious Wordperfect documents. The vulnerability serves as a reminder of the critical importance of input validation in document processing libraries and demonstrates how mathematical boundary conditions in memory management can create exploitable conditions that require careful attention to integer overflow and underflow scenarios. Organizations should also consider implementing network segmentation and access controls to limit exposure of systems that process untrusted documents, while monitoring for suspicious document access patterns that might indicate exploitation attempts.