If a user sends a request to a org.eclipse.jetty.servlets.CGI
Servlet for a binary with a space in its name, the servlet will escape the command by wrapping it in quotation marks. This wrapped command, plus an optional command prefix, will then be executed through a call to Runtime.exec. If the original binary name provided by the user contains a quotation mark followed by a space, the resulting command line will contain multiple tokens instead of one. For example, if a request references a binary called fileโ name โhere, the escaping algorithm will generate the command line string โfileโ name โhereโ, which will invoke the binary named file, not the one that the user requested.
if (execCmd.length() > 0 && execCmd.charAt(0) != '"' && execCmd.contains(" "))
execCmd = "\"" + execCmd + "\"";
The cgi-bin directory contains a binary named exec and a subdirectory named execโ commands, which contains a file called bin1. The user sends to the CGI servlet a request for the filename execโ commands/bin1. This request will pass the file existence check on lines 194 through 205. The servlet will add quotation marks around this filename, resulting in the command line string โexecโ commands/bin1โ. When this string is passed to Runtime.exec, instead of executing the bin1 binary, the server will execute the exec
binary with the argument commands/file1โ. In addition to being incorrect, this behavior may bypass alias checks, and it may cause other unintended behaviors if a command prefix is configured.
If the useFullPath configuration setting is off, the command need not pass the existence check. The attack would not rely on a binary and subdirectory having similar names, and the attack will succeed on a much wider variety of directory structures.
Users of the org.eclipse.jetty.servlets.CGI
Servlet with a very specific command structure may have the wrong command executed.
No patch.
In Jetty 9.x, 10.x, and 11.x the org.eclipse.jetty.servlets.CGI
has been deprecated.
In Jetty 12 (all environments) the org.eclipse.jetty.servlets.CGI
has been entirely removed.
The org.eclipse.jetty.servlets.CGI
Servlet should not be used. Fast CGI support is available instead.
github.com/advisories/GHSA-3gh6-v5v9-6v9j
github.com/eclipse/jetty.project/pull/9516
github.com/eclipse/jetty.project/pull/9888
github.com/eclipse/jetty.project/pull/9889
github.com/eclipse/jetty.project/security/advisories/GHSA-3gh6-v5v9-6v9j
lists.debian.org/debian-lts-announce/2023/09/msg00039.html
nvd.nist.gov/vuln/detail/CVE-2023-36479
www.debian.org/security/2023/dsa-5507