How severe is CVE-2021-43668?

CVE-2021-43668 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-43668 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43668?

CVE-2021-43668 affects Ethereum Go Ethereum. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43668?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-43668 published?

CVE-2021-43668 was published on 2021-11-18 and last updated on 2026-06-17.

CVE-2021-43668

CVE-2021-43668 is a medium-severity vulnerability in Ethereum Go Ethereum with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 2.1
EPSS exploit prediction: 0% (16th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Ethereum Go Ethereum
Published: 2021-11-18
Last modified: 2026-06-17

Description

Go-Ethereum 1.10.9 nodes crash (denial of service) after receiving a serial of messages and cannot be recovered. They will crash with "runtime error: invalid memory address or nil pointer dereference" and arise a SEGV signal.

Frequently asked questions

What is CVE-2021-43668?: Go-Ethereum 1.10.9 nodes crash (denial of service) after receiving a serial of messages and cannot be recovered. They will crash with "runtime error: invalid memory address or nil pointer dereference" and arise a SEGV signal.
How severe is CVE-2021-43668?: CVE-2021-43668 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-43668 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43668?: CVE-2021-43668 affects Ethereum Go Ethereum. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43668?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-43668 published?: CVE-2021-43668 was published on 2021-11-18 and last updated on 2026-06-17.

References

https://github.com/ethereum/go-ethereum/issues/23866

Affected products (1)

cpe:2.3:a:ethereum:go_ethereum:1.10.9:*:*:*:*:*:*:*

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