CVE-2021-40399 : Exploit Details and Defense Strategies

This CVE-2021-40399 article provides details about a high-severity vulnerability in WPS Office version 11.2.0.10351 that could lead to remote code execution.

Understanding CVE-2021-40399

CVE-2021-40399 is a use-after-free vulnerability in WPS Spreadsheets (ET) within WPS Office, allowing attackers to exploit a specially-crafted XLS file.

What is CVE-2021-40399?

Vulnerability Type: Use-After-Free (CWE-416)
CVSS Base Score: 8.8 (High)
Attack Vector: Network

The flaw enables an attacker to execute remote code by providing a malicious XLS file to the victim, triggering the use-after-free condition.

The Impact of CVE-2021-40399

This vulnerability has a high impact:

Confidentiality, integrity, and availability impacts are all high
Attack complexity is low, but user interaction is required

Technical Details of CVE-2021-40399

This section provides more insight into the technical aspects of the vulnerability.

Vulnerability Description

The vulnerability exists in WPS Spreadsheets (ET) within WPS Office, version 11.2.0.10351, allowing a specially-crafted XLS file to trigger a remote code execution due to a use-after-free condition.

Affected Systems and Versions

Product: WPS Office
Vendor: WPS
Affected Version: 11.2.0.10351

Exploitation Mechanism

Attack Complexity: Low
Privileges Required: None
Scope: Unchanged

Mitigation and Prevention

To mitigate the risks associated with CVE-2021-40399, users and organizations are advised to take the following steps:

Immediate Steps to Take

Update WPS Office to a non-vulnerable version
Avoid opening XLS files from untrusted sources
Implement network security measures

Long-Term Security Practices

Regularly update software and security patches
Conduct security awareness training for users

Patching and Updates

For official patches and updates, refer to the vendor's security advisory