CVE-2025-1240: WinZip Flaw Exposes System to Remote Code Execution Risks

A serious vulnerability has been found in WinZip, potentially allowing remote attackers to execute arbitrary code on affected systems. Identified as CVE-2025-1240, this flaw lies in how WinZip handles 7Z files and could be exploited if a user interacts with a malicious file or visits a harmful webpage.

With a CVSS score of 7.8, the vulnerability arises from inadequate validation of user-supplied data during the parsing of 7Z files. As the advisory explains, “The issue stems from improper validation of user data, which can lead to writing beyond the allocated buffer.” This out-of-bounds write could be exploited by an attacker to run code within the context of the WinZip process.

Although the flaw is significant, exploitation requires user interaction. The advisory notes that “User interaction is necessary for exploiting this vulnerability, as the target must open a malicious file or visit a harmful page.” Attackers would need to deceive users into opening a specially crafted 7Z file or visiting a compromised website containing the file. Social engineering techniques, such as phishing emails or malicious ads, could be used to trick victims into triggering the exploit.

The potential consequences of successful exploitation are severe. Remote code execution vulnerabilities can grant attackers full control of a victim’s system, allowing them to steal sensitive information, install malware, or even enlist the compromised machine in a botnet.

Fortunately, the CVE-2025-1240 vulnerability has been resolved in WinZip version 29.0. Users running earlier versions are strongly urged to update to version 29.0 immediately to safeguard against this threat. Given the serious nature of the vulnerability, taking prompt action is essential.

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