CVE-2019-15613 : Security Advisory and Response

Nextcloud Server 17.0.1 has a vulnerability that affects workflow rules due to a software glitch relying on file extensions instead of correctly assessing file mimetypes.

Understanding CVE-2019-15613

This CVE involves a bug in Nextcloud Server 17.0.1 that causes workflow rules to behave based on file extensions rather than accurately evaluating file mimetypes.

What is CVE-2019-15613?

The vulnerability in Nextcloud Server 17.0.1 results in workflow rules being influenced by file extensions, leading to improper assessment of file mimetypes.

The Impact of CVE-2019-15613

The vulnerability can potentially allow attackers to manipulate workflow rules and bypass security measures by exploiting the incorrect file mimetype assessment.

Technical Details of CVE-2019-15613

Nextcloud Server 17.0.1 vulnerability details and affected systems.

Vulnerability Description

A software glitch in Nextcloud Server 17.0.1 causes workflow rules to depend on file extensions rather than accurately assessing file mimetypes, leading to a security vulnerability.

Affected Systems and Versions

Product: Nextcloud Server
Version: 17.0.2

Exploitation Mechanism

Attackers can exploit this vulnerability by manipulating file extensions to bypass security controls and potentially execute malicious actions.

Mitigation and Prevention

Steps to mitigate and prevent exploitation of CVE-2019-15613.

Immediate Steps to Take

Update Nextcloud Server to version 17.0.2 or later to patch the vulnerability.
Implement file type validation based on mimetypes rather than extensions.

Long-Term Security Practices

Regularly update and patch software to address known vulnerabilities.
Conduct security assessments to identify and remediate similar issues in the future.

Patching and Updates

Stay informed about security advisories from Nextcloud and apply patches promptly to secure the system.