CVE-2008-0113 in Office
Summary
by MITRE
Unspecified vulnerability in Microsoft Office Excel Viewer 2003 up to SP3 allows user-assisted remote attackers to execute arbitrary code via an Excel document with malformed cell comments that trigger memory corruption from an "allocation error," aka "Microsoft Office Cell Parsing Memory Corruption Vulnerability."
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Analysis
by VulDB Data Team • 08/07/2019
This vulnerability resides within Microsoft Office Excel Viewer 2003 and its subsequent service packs up to SP3, representing a critical memory corruption flaw that enables remote code execution under specific conditions. The vulnerability specifically manifests when processing Excel documents containing malformed cell comments that trigger allocation errors during memory management operations. This type of vulnerability falls under the broader category of memory corruption issues that are commonly classified as CWE-122, which deals with heap-based buffer overflows and memory allocation errors. The flaw represents a classic example of how improper input validation can lead to severe security implications in office productivity software.
The technical mechanism behind this vulnerability involves the Excel Viewer's cell parsing routine encountering malformed cell comments within Excel documents. When the application attempts to allocate memory for processing these comments, an allocation error occurs that results in memory corruption. This memory corruption can be exploited by attackers to overwrite critical memory locations, potentially allowing them to execute arbitrary code with the privileges of the affected user. The vulnerability requires user interaction to be exploited, as the target must open the malicious Excel document, making it a user-assisted remote code execution vulnerability. This classification aligns with ATT&CK technique T1203, which covers exploitation for execution through malicious file delivery.
The operational impact of this vulnerability extends beyond simple code execution, as it can lead to complete system compromise when attackers successfully exploit the memory corruption. An attacker could potentially gain unauthorized access to sensitive data, install malware, or establish persistent backdoors within the victim's system. The widespread use of Excel Viewer 2003 in corporate and enterprise environments makes this vulnerability particularly dangerous, as it could affect numerous systems across different organizations. Organizations running these older versions of Excel Viewer face significant risk exposure, especially in environments where users regularly open documents from untrusted sources or external parties.
Mitigation strategies for this vulnerability should focus on immediate remediation through Microsoft's security updates and patches, as well as implementing administrative controls to prevent execution of potentially malicious documents. Organizations should consider implementing application whitelisting policies to restrict execution of Office Viewer applications, particularly in high-risk environments. Network-based protections such as email filtering and web application firewalls can help prevent delivery of malicious Excel documents to end users. The vulnerability also underscores the importance of maintaining up-to-date software inventory and implementing robust patch management processes to address similar memory corruption vulnerabilities that may exist in legacy software versions. Given the nature of the flaw, organizations should also consider network segmentation and user privilege controls to limit potential damage from successful exploitation attempts.