CVE-2026-39461

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However, it does not verify that its socket descriptor fits within select(2)'s descriptor set size limit of FD_SETSIZE (1024).\n\nAn attacker able to cause an application using libcasper(3) to allocate large file descriptors, e.g., by opening many descriptors and executing a program which is not careful to close them upon startup, may trigger stack corruption. If the target application runs with setuid root privileges, this could be used to escalate local privileges."}, {"lang": "es", "value": "libcasper(3) se comunica con procesos auxiliares a trav\u00e9s de sockets de dominio UNIX, y utiliza la llamada al sistema select(2) para esperar a que los datos est\u00e9n disponibles. Sin embargo, no verifica que su descriptor de socket encaje dentro del l\u00edmite de tama\u00f1o del conjunto de descriptores de select(2) de FD_SETSIZE (1024).\n\nUn atacante capaz de hacer que una aplicaci\u00f3n que utiliza libcasper(3) asigne descriptores de archivo grandes, por ejemplo, abriendo muchos descriptores y ejecutando un programa que no tiene cuidado de cerrarlos al inicio, puede desencadenar una corrupci\u00f3n de la pila. Si la aplicaci\u00f3n objetivo se ejecuta con privilegios setuid root, esto podr\u00eda usarse para escalar privilegios locales."}], "id": "CVE-2026-39461", "lastModified": "2026-07-23T16:10:00.137", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 8.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 2.0, "impactScore": 6.0, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-39461", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-05-21T00:00:00+00:00", "version": "2.0.3"}}]}, "published": "2026-05-21T10:16:25.320", "references": [{"source": "secteam@freebsd.org", "tags": ["Vendor Advisory"], "url": "https://security.freebsd.org/advisories/FreeBSD-SA-26:22.libcasper.asc"}], "sourceIdentifier": "secteam@freebsd.org", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-121"}], "source": "secteam@freebsd.org", "type": "Secondary"}]}

{}

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