CVE-2009-2570 in WinFax Pro
Summary
by MITRE
Stack-based buffer overflow in the Symantec.FaxViewerControl.1 ActiveX control in WinFax\DCCFAXVW.DLL in Symantec WinFax Pro 10.03 allows remote attackers to execute arbitrary code via a long argument to the AppendFax method.
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Analysis
by VulDB Data Team • 11/17/2025
The vulnerability identified as CVE-2009-2570 represents a critical stack-based buffer overflow flaw within the Symantec WinFax Pro 10.03 software suite, specifically affecting the Symantec.FaxViewerControl.1 ActiveX control component. This vulnerability exists within the DCCFAXVW.DLL library that handles fax viewing functionality, creating a dangerous condition where malicious input can overwrite adjacent memory locations on the stack. The flaw is particularly concerning as it affects a widely deployed enterprise fax solution that was commonly used in business environments for document management and communication.
The technical implementation of this vulnerability stems from improper input validation within the AppendFax method of the ActiveX control. When a remote attacker provides an excessively long argument string to this method, the control fails to properly bounds-check the input before copying it to a fixed-size stack buffer. This classic buffer overflow condition allows an attacker to overwrite the return address and other critical stack variables, potentially enabling arbitrary code execution with the privileges of the affected application. The vulnerability is categorized under CWE-121 as a stack-based buffer overflow, which represents a well-known and dangerous class of memory corruption vulnerabilities that have been extensively documented in the cybersecurity community.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with a potential pathway for complete system compromise within environments where Symantec WinFax Pro is installed. Organizations running this software are at risk of unauthorized access, data exfiltration, and potential lateral movement within their network infrastructure. The attack vector is particularly dangerous because it can be exploited remotely through web-based interfaces or malicious websites that embed the vulnerable ActiveX control, making it an attractive target for widespread exploitation campaigns. This vulnerability directly aligns with ATT&CK technique T1203, which covers exploitation of remote services, and T1059, which encompasses the execution of malicious code through compromised applications.
Mitigation strategies for this vulnerability should include immediate patching of Symantec WinFax Pro 10.03 to the latest available version that addresses the buffer overflow condition. System administrators should also implement application whitelisting policies to prevent execution of untrusted ActiveX controls and consider disabling ActiveX controls in web browsers where possible. Network segmentation and intrusion detection systems should be configured to monitor for suspicious activity related to fax processing and ActiveX control usage. Additionally, organizations should conduct comprehensive vulnerability assessments to identify all instances of the vulnerable software and ensure that proper security configurations are in place to prevent exploitation attempts. The vulnerability highlights the importance of proper input validation and memory management practices in software development, particularly for components that handle untrusted input from network sources.