CVE-2018-20421

Public Exploit

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.

Category

7.5
CVSS
Severity: High
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.33%
Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/ethereum/go-ethereum/issues/18289 third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2018-20421?
CVE-2018-20421 has been scored as a high severity vulnerability.
How to fix CVE-2018-20421?
To fix CVE-2018-20421, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2018-20421 being actively exploited in the wild?
It is possible that CVE-2018-20421 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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