CVE-2026-33436 PUBLISHED

Stirling-PDF: Reflected XSS through crafted filename in file upload functionality

Assigner: GitHub_M
Reserved: 19.03.2026 Published: 17.04.2026 Updated: 17.04.2026

Stirling-PDF is a locally hosted web application that facilitates various operations on PDF files. In versions prior to 2.0.0, file upload endpoints render user-supplied filenames directly into HTML using unsafe methods like innerHTML without sanitization. An attacker can craft a file with a malicious filename containing JavaScript that executes in the uploading user's browser context, resulting in reflected XSS. The issue affects numerous upload endpoints across the application. The issue has been fixed in version 2.0.0.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N
CVSS Score: 3.1

Product Status

Vendor Stirling-Tools
Product Stirling-PDF
Versions
  • Version < 2.0.0 is affected

References

Problem Types

  • CWE-20: Improper Input Validation CWE
  • CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') CWE
  • CWE-116: Improper Encoding or Escaping of Output CWE