Executive brief
Network File System (NFS) is a protocol used to share files and folders across a network. A vulnerability in certain implementations allows unauthorized users to navigate outside of the specifically shared folders by using parent directory commands. This could lead to the exposure of sensitive system files or data that was never intended to be shared publicly.
Technical details
This vulnerability is a directory traversal flaw within certain NFS implementations. By utilizing the 'cd ..' command or equivalent path traversal sequences, a remote attacker can escape the root of the exported file system (the 'export'). This occurs because the service fails to properly validate or restrict directory navigation requests to the boundaries of the defined share. An attacker can leverage this to gain unauthorized read access to files and directories on the host system that are outside the intended scope of the NFS export. The attack is reachable over the network and typically does not require authentication depending on the export configuration.
Affected products
- Generic NFS
Timeline
- 1997-01-01: disclosed