Common Vulnerabilities and Exposures assigned an identifier CVE-2008-1891 to the following vulnerability:
Directory traversal vulnerability in WEBrick in Ruby 1.9.0 and earlier, when using NTFS or FAT filesystems, allows remote attackers to read arbitrary CGI files via a trailing (1) + (plus), (2) %2b (encoded plus), (3) . (dot), (4) %2e (encoded dot), or (5) %20 (encoded space) character in the URI, possibly related to the WEBrick::HTTPServlet::FileHandler and WEBrick::HTTPServer.new functionality and the :DocumentRoot option.
This issue only affects systems where Ruby WEBrick is used to serve content from
certain filesystems that treat certain file names as identical (e.g.
'file.name.' is same file as 'file.name'). Out of the mentioned filesystems,
only FAT in supported by Red Hat Enterprise Linux, but it's unlikely to be used
in a real deployments as storage for web content.
Ruby packages as shipped in Red Hat Enterprise Linux 2.1 and 3 do not contain
WEBrick and therefore are not affected by this problem.
Patch applied in ruby SVN trunk:
ruby-220.127.116.11-1.fc8 has been pushed to the Fedora 8 stable repository. If problems still persist, please make note of it in this bug report.
ruby-18.104.22.168-1.fc9 has been pushed to the Fedora 9 stable repository. If problems still persist, please make note of it in this bug report.
The risks associated with fixing this flaw outweigh the benefits of the fix. Red Hat does not plan to fix this flaw in Red Hat Enterprise Linux.