Ruby · Rack · CVE-2020-8161
**Name of the Vulnerable Software and Affected Versions**
rack versions prior to 2.2.0
**Description**
A directory traversal issue exists in the Rack::Directory app, allowing an attacker to perform a directory traversal attack, which could result in information disclosure. The vulnerability is related to the `check forbidden` function in the `rack/directory.rb` module, which incorrectly restricts the directory path name. This could allow a remote attacker to access confidential data.
**Recommendations**
For versions prior to 2.2.0, update to version 2.2.0 or later to resolve the issue.
As a temporary workaround, consider restricting access to the Rack::Directory app until a patch is available.