CVE-2006-3653 in Works
Summary
by MITRE
wksss.exe 8.4.702.0 in Microsoft Works Spreadsheet 8.0 allows remote attackers to cause a denial of service (CPU consumption or crash) via crafted (1) Works, (2) Excel, and (3) Lotus 1-2-3 files.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 07/31/2018
The vulnerability identified as CVE-2006-3653 affects wksss.exe version 8.4.702.0 in Microsoft Works Spreadsheet 8.0, representing a significant denial of service weakness that can be exploited remotely through maliciously crafted spreadsheet files. This vulnerability specifically targets the file format parsing mechanisms within the spreadsheet application, where the flaw manifests when processing Works, Excel, and Lotus 1-2-3 formatted files. The attack vector leverages the application's insufficient input validation and error handling when encountering malformed or specially crafted data structures within these file formats, creating a scenario where legitimate system resources become consumed excessively or the application crashes entirely.
The technical exploitation of this vulnerability involves the remote attacker crafting malicious files that contain malformed data structures designed to trigger specific parsing errors within the wksss.exe process. When the vulnerable Microsoft Works Spreadsheet application attempts to open these crafted files, the parsing routines fail to properly handle the malformed input, leading to either infinite loops in the processing logic or memory corruption that ultimately results in system resource exhaustion. This behavior aligns with CWE-129, which describes improper validation of array indices, and CWE-131, which covers incorrect calculation of buffer sizes. The vulnerability represents a classic example of insufficient input validation where the application fails to properly sanitize or validate the structure and content of imported files before processing them.
The operational impact of this vulnerability extends beyond simple system unavailability, as it can be leveraged to consume excessive CPU resources or cause complete application crashes, effectively rendering the affected system unusable for spreadsheet operations. Attackers can exploit this weakness to launch denial of service attacks against systems running vulnerable versions of Microsoft Works Spreadsheet, potentially affecting business productivity and creating opportunities for more sophisticated attacks. The vulnerability's remote exploitation capability means that attackers do not require physical access to the target system, making it particularly dangerous in networked environments where users might inadvertently open malicious files received through email attachments, file sharing systems, or web downloads. This scenario represents a key entry point for attackers seeking to establish persistent access or disrupt business operations.
Mitigation strategies for this vulnerability should focus on immediate patch deployment through Microsoft's security updates, as the company would have released a fix addressing the specific parsing flaws in the wksss.exe component. Organizations should also implement strict file validation policies, including content inspection and sandboxing of suspicious files before processing them within the application. Network-level controls such as email filtering and web content filtering can help prevent the delivery of malicious files to end users, while user education regarding safe file handling practices remains essential. The vulnerability demonstrates the importance of proper input validation and error handling in software applications, aligning with ATT&CK technique T1499.004 for network denial of service and emphasizing the need for robust software security practices. System administrators should consider implementing application whitelisting to prevent execution of untrusted spreadsheet files and ensure that all Microsoft Works installations are updated to versions that address this specific vulnerability.