CVE-2026-55781

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{"affected": [{"affectedData": [{"product": "NanaZip", "vendor": "M2Team", "versions": [{"status": "affected", "version": "< 6.5.1749.0"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "NanaZip is the 7-Zip derivative intended for the modern Windows experience. Prior to 6.5.1749.0, NanaZip's UFS and FFS image handler in NanaZip.Codecs.Archive.Ufs.cpp validates the superblock block size only against the MINBSIZE lower bound and does not validate the fs_fsize fragment size, allowing attacker-controlled 32-bit fields to flow into indirect-block, directory, and extraction buffer allocations. A tiny crafted UFS image can force multi-gigabyte allocations during open or extraction, causing memory exhaustion or process termination. This issue is fixed in version 6.5.1749.0."}, {"lang": "es", "value": "NanaZip es el derivado de 7-Zip destinado a la experiencia moderna de Windows. Antes de la versi\u00f3n 6.5.1749.0, el gestor de im\u00e1genes UFS y FFS de NanaZip en NanaZip.Codecs.Archive.Ufs.cpp valida el tama\u00f1o de bloque del superbloque solo contra el l\u00edmite inferior MINBSIZE y no valida el tama\u00f1o de fragmento fs_fsize, permitiendo que campos de 32 bits controlados por el atacante fluyan hacia asignaciones de b\u00fafer de bloque indirecto, directorio y extracci\u00f3n. Una peque\u00f1a imagen UFS manipulada puede forzar asignaciones de varios gigabytes durante la apertura o extracci\u00f3n, causando agotamiento de memoria o terminaci\u00f3n del proceso. Este problema est\u00e1 solucionado en la versi\u00f3n 6.5.1749.0."}], "id": "CVE-2026-55781", "lastModified": "2026-10-25T15:10:00.147", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "LOCAL", "availabilityRequirement": "NOT_DEFINED", "baseScore": 2.4, "baseSeverity": "LOW", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "LOW", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "PASSIVE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:L/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", "version": "4.0", "vulnAvailabilityImpact": "LOW", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-55781", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-07-10T20:46:24.470182Z", "version": "2.0.3"}}]}, "published": "2026-07-10T17:16:59.883", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/M2Team/NanaZip/commit/6415b6bff70bc9c486b49cbbc1982724c67f8338"}, {"source": "security-advisories@github.com", "url": "https://github.com/M2Team/NanaZip/releases/tag/6.5.1749.0"}, {"source": "security-advisories@github.com", "url": "https://github.com/M2Team/NanaZip/security/advisories/GHSA-m34h-jf84-m74h"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-400"}, {"lang": "en", "value": "CWE-789"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,6.5.1749.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "NanaZip", "source": "cna", "vendor": "M2Team"}, "product": "nanazip", "vendor": "m2team"}], "created": "2026-07-10T18:30:16.428363+00:00", "updated": "2026-08-01T12:30:04.132380+00:00", "vendors": ["m2team", "m2team$PRODUCT$nanazip"]}