CVE-2018-20421
Estado: ModificadaAlta (7.5)—
Go Ethereum (aka geth) 1.8.19 allows attackers to cause a denial of service (memory consumption) by rewriting the length of a dynamic array in memory, and then writing data to a single memory location with a large index number, as demonstrated by use of "assembly { mstore }" followed by a "c[0xC800000] = 0xFF" assignment.
CVSS
- Versión: 3.0
- Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.46%
- Percentil entre todas las CVEs puntuadas: 73
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-770
Referencias
JSON original (NVD)
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"published": "2018-12-24T03:29:00.353",
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"url": "https://github.com/ethereum/go-ethereum/issues/18289",
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"value": "Go Ethereum (también conocido como geth) 1.8.19 permite que los atacantes provoquen una denegación de servicio (consumo de memoria) mediante la reescritura de la longitud de un array dinámico en la memoria y, a continuación, la escritura de datos a una única ubicación de memoria con un número de índice largo. Esto queda demostrado por el uso de \"assembly { mstore }\", seguido por una asignación \"c[0xC800000] = 0xFF\"."
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"lastModified": "2026-06-17T01:52:48.627",
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