CVE-2025-50327 in ZPAQFRANZ
Summary
by MITRE • 07/23/2026
An issue in Franco Corbelli ZPAQFRANZ v.61.3 and before allows a remote attacker to escalate privileges and execute arbitrary code via a bypass of the Mark-of-the-Web protection mechanism
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Analysis
by VulDB Data Team • 07/23/2026
The vulnerability identified in Franco Corbelli ZPAQFRANZ version 61.3 and earlier represents a critical privilege escalation flaw that undermines fundamental security protections designed to prevent unauthorized code execution. This issue stems from a failure in the application's implementation of the Mark-of-the-Web protection mechanism, which serves as a crucial defense against potentially malicious files downloaded from the internet. The Mark-of-the-Web is a Windows security feature that applies security labels to files downloaded from web sources, preventing them from executing with elevated privileges and restricting their access to system resources. When this protection is bypassed, it creates an attack vector that allows remote adversaries to escalate their privileges and execute arbitrary code on affected systems.
The technical flaw manifests in the application's improper handling of file execution contexts, where the software fails to properly validate or enforce security boundaries that should prevent downloaded files from gaining elevated permissions. This vulnerability operates at the intersection of multiple security domains including file execution control, privilege management, and web-based attack surface mitigation. The bypass mechanism likely involves manipulation of file attributes, registry entries, or process execution flows that normally would be restricted by Windows security policies. Attackers can leverage this weakness to execute malicious payloads with system-level privileges, effectively circumventing the standard security controls that protect against untrusted code execution.
The operational impact of this vulnerability extends beyond simple privilege escalation to encompass full system compromise capabilities for remote attackers. Once successfully exploited, the vulnerability allows adversaries to execute arbitrary code with elevated privileges, potentially enabling them to install persistent backdoors, exfiltrate sensitive data, modify system configurations, or establish covert communication channels. This represents a severe threat to enterprise environments where ZPAQFRANZ may be used for file compression and archiving operations, as it could allow attackers to compromise systems through seemingly benign file handling activities. The remote nature of the attack means that exploitation can occur without physical access to target systems, making it particularly dangerous in networked environments.
Mitigation strategies for this vulnerability should focus on immediate patching of affected versions and implementation of additional security controls to reduce attack surface. Organizations should prioritize updating to the latest version of ZPAQFRANZ where the Mark-of-the-Web bypass has been addressed through proper validation of file execution contexts. System administrators should implement enhanced monitoring of file execution activities, particularly those involving compressed archives or downloaded files that may trigger privilege escalation vectors. The vulnerability aligns with CWE-284 (Improper Access Control) and relates to ATT&CK techniques such as privilege escalation through exploitation of software vulnerabilities. Additional defensive measures include implementing application whitelisting policies, configuring proper file execution restrictions, and establishing network segmentation to limit the potential impact of successful exploitation attempts.