CVE-2018-18315 : What You Need to Know

In lemon 1.9.0, a vulnerability in com/mossle/cdn/CdnController.java allows attackers to upload arbitrary files due to inadequate validation.

Understanding CVE-2018-18315

What is CVE-2018-18315?

In lemon 1.9.0, attackers can exploit a vulnerability in com/mossle/cdn/CdnController.java to upload any files they want. The vulnerability lies in the copyMultipartFileToFile method in CdnUtils, which only checks for the presence of the substring "../" and fails to validate the file type and spaceName parameter.

The Impact of CVE-2018-18315

This vulnerability enables malicious actors to upload unauthorized files, potentially leading to unauthorized access or execution of arbitrary code on the affected system.

Technical Details of CVE-2018-18315

Vulnerability Description

The flaw in com/mossle/cdn/CdnController.java allows attackers to bypass file upload restrictions by exploiting the copyMultipartFileToFile method's insufficient validation.

Affected Systems and Versions

Product: Lemon 1.9.0
Vendor: Not applicable
Version: Not applicable

Exploitation Mechanism

Attackers can abuse the vulnerability by uploading files with malicious content, leveraging the lack of proper validation in the copyMultipartFileToFile method.

Mitigation and Prevention

Immediate Steps to Take

Implement input validation to ensure uploaded files adhere to expected formats.
Regularly monitor file uploads for suspicious activities.
Apply security patches or updates provided by the software vendor.

Long-Term Security Practices

Conduct regular security assessments and penetration testing to identify and address vulnerabilities.
Educate users on safe file upload practices and potential risks associated with unauthorized uploads.

Patching and Updates

Ensure that the lemon software is updated to the latest version that includes fixes for the vulnerability.