CVE-2017-0884 : Exploit Details and Defense Strategies

Nextcloud Server versions prior to 9.0.55 and 10.0.2 have a vulnerability that allows the creation of folders in read-only directories, even without proper permissions. This flaw in the file caching system enables an authenticated attacker to generate empty folders within a shared folder.

Understanding CVE-2017-0884

This CVE affects Nextcloud Server versions before 9.0.55 and 10.0.2, allowing unauthorized creation of folders in read-only directories.

What is CVE-2017-0884?

The vulnerability in Nextcloud Server versions prior to 9.0.55 and 10.0.2 permits the creation of folders in read-only directories by authenticated attackers, exploiting a flaw in the file caching system.

The Impact of CVE-2017-0884

Authenticated attackers can create empty folders within shared folders without proper permissions.
The vulnerability affects folders and files accessible with at least read-only permissions.

Technical Details of CVE-2017-0884

Nextcloud Server vulnerability details and affected systems.

Vulnerability Description

The flaw allows the creation of folders in read-only directories by exploiting a logical error in the file caching layer.

Affected Systems and Versions

Product: Nextcloud Server
Vendor: Nextcloud
Versions Affected: All versions before 9.0.55 and 10.0.2

Exploitation Mechanism

Attackers with authenticated access can exploit the vulnerability to create empty folders within shared folders.

Mitigation and Prevention

Protecting systems from CVE-2017-0884.

Immediate Steps to Take

Update Nextcloud Server to versions 9.0.55 or 10.0.2 to mitigate the vulnerability.
Monitor and restrict access permissions to prevent unauthorized folder creation.

Long-Term Security Practices

Regularly review and update file permissions to limit unauthorized actions.
Conduct security audits to identify and address potential vulnerabilities.

Patching and Updates

Apply patches and updates provided by Nextcloud to address the vulnerability.