CVE-2020-5221 Explained : Impact and Mitigation

In uftpd before 2.11, a Directory Traversal (Chroot Escape) vulnerability exists, allowing unauthenticated users to perform malicious actions on the filesystem. The issue has been fixed in version 2.11.

Understanding CVE-2020-5221

This CVE involves a security vulnerability in uftpd that enables unauthenticated users to execute a directory traversal attack, potentially leading to unauthorized access to sensitive files and directories.

What is CVE-2020-5221?

The vulnerability in uftpd before version 2.11 allows unauthenticated users to perform a directory traversal attack using various FTP commands.
Attackers can read and write to arbitrary locations on the filesystem due to the absence of a properly implemented chroot jail in compose_abspath().

The Impact of CVE-2020-5221

CVSS Score: 6.5 (Medium)
Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: Required
Scope: Changed
Confidentiality Impact: Low
Integrity Impact: Low
Availability Impact: Low

Technical Details of CVE-2020-5221

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability allows unauthenticated users to bypass security restrictions and access unauthorized areas of the filesystem.

Affected Systems and Versions

Affected Product: uftpd
Vendor: Troglobit
Affected Versions: < 2.11

Exploitation Mechanism

Attackers exploit the lack of proper chroot jail implementation in compose_abspath() to navigate the filesystem and perform unauthorized actions.

Mitigation and Prevention

Protect your systems from CVE-2020-5221 with the following steps:

Immediate Steps to Take

Update uftpd to version 2.11 or newer to eliminate the vulnerability.
Implement proper access controls and authentication mechanisms to restrict unauthorized access.

Long-Term Security Practices

Regularly monitor and audit file system access to detect any suspicious activities.
Educate users on secure FTP practices and the risks associated with unauthenticated access.

Patching and Updates

Stay informed about security advisories and updates from Troglobit to address any future vulnerabilities.