Red Hat GVfs FTP Backend Command Injection Vulnerability

A command injection vulnerability has been identified in the FTP backend of GVfs (GNOME Virtual File System). This issue arises from improper input validation of file paths, allowing remote attackers to inject arbitrary FTP commands. The vulnerability is exploited by crafting file paths that include carriage return and line feed (CRLF) sequences. These unsanitized sequences can terminate existing FTP commands and introduce new ones, potentially leading to arbitrary code execution or other serious consequences.

Impact

Exploitation of this vulnerability allows for arbitrary FTP command injection, with the potential for arbitrary code execution or other severe impacts, depending on the injected commands and the context in which they are executed.

Reproduction

The vulnerability can be reproduced by supplying a file path to the GVfs FTP backend that includes CRLF sequences. This can be done through applications that use GVfs for FTP access, typically in desktop environments. The crafted path will be processed by the GVfs FTP backend, where the CRLF sequences can terminate the intended FTP command and inject arbitrary commands instead.

Remediation

Users are advised to avoid connecting to untrusted FTP servers or opening FTP links from unverified sources. Implementing network-level restrictions to limit outbound connections to trusted FTP servers can also help mitigate the risk. If the GVfs FTP backend is not essential, consider removing or disabling it, although this may impact other desktop features that rely on GVfs for FTP access.