CVE-2018-20421

HighCVSS 7.5/10Last modified Jun 17, 2026

Description

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.

Metrics

CVSS 3.0 7.5/10CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
Dec 24, 2018
Last modified
Jun 17, 2026
NVD status
Modified

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CVE-2018-20421: High severity, CVSS 7.5 | Vulnix