CVE-2026-76845

{"id": "CVE-2026-76845", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-76845", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-08-24T16:25:27.278594Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 4.0, "exploitabilityScore": 2.0}], "cvssMetricV40": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 6.8, "Automatable": "NOT_DEFINED", "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "disclosure@vulncheck.com", "affectedData": [{"vendor": "cthackers", "product": "adm-zip", "versions": [{"status": "affected", "version": "0.5.9", "versionType": "semver", "lessThanOrEqual": "0.6.0"}], "packageURL": "pkg:npm/adm-zip", "packageName": "adm-zip", "collectionURL": "https://www.npmjs.com/package/adm-zip", "defaultStatus": "unaffected"}]}], "published": "2026-08-24T14:17:02.423", "references": [{"url": "https://github.com/cthackers/adm-zip", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/cthackers/adm-zip/blob/v0.6.0/util/utils.js", "source": "disclosure@vulncheck.com"}, {"url": "https://www.vulncheck.com/advisories/adm-zip-through-arbitrary-file-overwrite-via-symlink-following-on-extraction", "source": "disclosure@vulncheck.com"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "description": [{"lang": "en", "value": "CWE-59"}]}], "descriptions": [{"lang": "en", "value": "adm-zip 0.5.9 through 0.6.0 follows symbolic links at the extraction destination. Utils.sanitize in util/utils.js enforces containment by comparing only the string form of an archive entry name against the resolved extraction root, and Utils.writeFileTo opens the computed destination with fs.openSync(path, \"w\", 0o666), which resolves symbolic links and carries neither O_NOFOLLOW nor a pre-write fs.lstatSync check. When a path component at the destination already exists as a symbolic link pointing outside the extraction root, extractAllTo, extractAllToAsync and extractEntryTo write the entry contents through that link and then chmod its target, placing attacker-controlled content in a file outside the root without any traversal sequence appearing in the archive. Reaching the write requires overwrite to be enabled, because the preceding fs.existsSync check also resolves the link and otherwise declines. An attacker able to create a symbolic link inside a shared, reused or predictable extraction directory, such as a temporary directory or a continuous integration workspace, can overwrite any file the extracting process is permitted to write."}, {"lang": "es", "value": "adm-zip 0.5.9 a 0.6.0 sigue enlaces simb\u00f3licos en el destino de extracci\u00f3n. Utils.sanitize en util/utils.js impone la contenci\u00f3n comparando solo la forma de cadena de un nombre de entrada de archivo contra la ra\u00edz de extracci\u00f3n resuelta, y Utils.writeFileTo abre el destino calculado con fs.openSync(path, 'w', 0o666), que resuelve enlaces simb\u00f3licos y no lleva ni O_NOFOLLOW ni una comprobaci\u00f3n fs.lstatSync previa a la escritura. Cuando un componente de ruta en el destino ya existe como un enlace simb\u00f3lico que apunta fuera de la ra\u00edz de extracci\u00f3n, extractAllTo, extractAllToAsync y extractEntryTo escriben el contenido de la entrada a trav\u00e9s de ese enlace y luego chmod su objetivo, colocando contenido controlado por el atacante en un archivo fuera de la ra\u00edz sin que aparezca ninguna secuencia de recorrido en el archivo. Alcanzar la escritura requiere que la sobrescritura est\u00e9 habilitada, porque la comprobaci\u00f3n fs.existsSync precedente tambi\u00e9n resuelve el enlace y, de lo contrario, declina. Un atacante capaz de crear un enlace simb\u00f3lico dentro de un directorio de extracci\u00f3n compartido, reutilizado o predecible, como un directorio temporal o un espacio de trabajo de integraci\u00f3n continua, puede sobrescribir cualquier archivo que el proceso de extracci\u00f3n tenga permiso para escribir."}], "lastModified": "2026-10-12T15:10:00.207", "sourceIdentifier": "disclosure@vulncheck.com"}