CVE-2026-33436: CWE-20: Improper Input Validation in Stirling-Tools Stirling-PDF
CVE-2026-33436 is a reflected cross-site scripting (XSS) vulnerability in Stirling-PDF versions prior to 2. 0. 0. The vulnerability arises because file upload endpoints render user-supplied filenames directly into HTML using unsafe methods like innerHTML without sanitization. This allows an attacker to craft a malicious filename containing JavaScript that executes in the uploading user's browser context. The issue affects multiple upload endpoints in the application. The vulnerability has been fixed in version 2. 0. 0.
AI Analysis
Technical Summary
Stirling-PDF, a locally hosted web application for PDF operations, suffers from improper input validation (CWE-20) and unsafe output encoding (CWE-79, CWE-116) in versions before 2.0.0. Specifically, the application renders user-supplied filenames in HTML using innerHTML without sanitization, enabling reflected XSS attacks. An attacker can exploit this by uploading a file with a malicious filename that executes JavaScript in the victim's browser. Multiple upload endpoints are affected. The vulnerability is addressed in version 2.0.0.
Potential Impact
Successful exploitation results in reflected cross-site scripting, allowing execution of attacker-controlled JavaScript in the context of the uploading user's browser. The CVSS score is 3.1 (low severity), indicating limited impact primarily on confidentiality with no direct impact on integrity or availability. There are no known exploits in the wild.
Mitigation Recommendations
Upgrade Stirling-PDF to version 2.0.0 or later, where this vulnerability has been fixed. Since the vendor advisory confirms the issue is resolved in this version, applying this official fix is the recommended remediation. No additional mitigations are indicated.
CVE-2026-33436: CWE-20: Improper Input Validation in Stirling-Tools Stirling-PDF
Description
CVE-2026-33436 is a reflected cross-site scripting (XSS) vulnerability in Stirling-PDF versions prior to 2. 0. 0. The vulnerability arises because file upload endpoints render user-supplied filenames directly into HTML using unsafe methods like innerHTML without sanitization. This allows an attacker to craft a malicious filename containing JavaScript that executes in the uploading user's browser context. The issue affects multiple upload endpoints in the application. The vulnerability has been fixed in version 2. 0. 0.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Stirling-PDF, a locally hosted web application for PDF operations, suffers from improper input validation (CWE-20) and unsafe output encoding (CWE-79, CWE-116) in versions before 2.0.0. Specifically, the application renders user-supplied filenames in HTML using innerHTML without sanitization, enabling reflected XSS attacks. An attacker can exploit this by uploading a file with a malicious filename that executes JavaScript in the victim's browser. Multiple upload endpoints are affected. The vulnerability is addressed in version 2.0.0.
Potential Impact
Successful exploitation results in reflected cross-site scripting, allowing execution of attacker-controlled JavaScript in the context of the uploading user's browser. The CVSS score is 3.1 (low severity), indicating limited impact primarily on confidentiality with no direct impact on integrity or availability. There are no known exploits in the wild.
Mitigation Recommendations
Upgrade Stirling-PDF to version 2.0.0 or later, where this vulnerability has been fixed. Since the vendor advisory confirms the issue is resolved in this version, applying this official fix is the recommended remediation. No additional mitigations are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-03-19T18:45:22.436Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e29db8bdfbbecc598ee1b5
Added to database: 4/17/2026, 8:53:12 PM
Last enriched: 4/17/2026, 9:08:43 PM
Last updated: 4/18/2026, 5:13:50 AM
Views: 7
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