CVE-2026-48711

A flaw was found in SSHFS, a network filesystem client. An attacker can exploit this vulnerability by providing a specially crafted mount source that includes argument delimiters. This improper handling of the mount source allows for argument injection, leading to the execution of arbitrary commands on the system as the user running SSHFS. This occurs before any connection or authentication, posing a significant security risk.

A flaw was found in SSHFS, a network filesystem client for connecting to SSH servers. SSHFS accepts a bracketed mount source such as [-oProxyCommand=CMD]:/path and removes the brackets during parsing, leaving a host value that begins with a dash. This value is passed directly to ssh as a command-line argument, causing ssh to interpret it as an option rather than a hostname. When combined with a path-valued sftp_server configuration, this allows an attacker who can control the mount source parameter to inject a ProxyCommand that executes arbitrary local commands as the user running SSHFS, before any SSH connection or authentication occurs. This vulnerability affects applications or wrappers that pass untrusted input as the sshfs mount source.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Update fuse-sshfs to version 3.7.6 or later. As a workaround, ensure that mount source parameters passed to sshfs come only from trusted sources and validate input to reject mount sources beginning with brackets or dashes. Applications wrapping sshfs should implement strict input validation before invoking the command.