How severe is CVE-2020-17516?

CVE-2020-17516 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2020-17516 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-17516?

CVE-2020-17516 affects Apache Cassandra. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-17516?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-17516 published?

CVE-2020-17516 was published on 2021-02-03 and last updated on 2026-06-17.

CVE-2020-17516

CVE-2020-17516 is a high-severity vulnerability in Apache Cassandra with a CVSS 3.x base score of 7.5. 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-290.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 4.3
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-290
Affected product: Apache Cassandra
Published: 2021-02-03
Last modified: 2026-06-17

Description

Apache Cassandra versions 2.1.0 to 2.1.22, 2.2.0 to 2.2.19, 3.0.0 to 3.0.23, and 3.11.0 to 3.11.9, when using 'dc' or 'rack' internode_encryption setting, allows both encrypted and unencrypted internode connections. A misconfigured node or a malicious user can use the unencrypted connection despite not being in the same rack or dc, and bypass mutual TLS requirement.

Frequently asked questions

What is CVE-2020-17516?: Apache Cassandra versions 2.1.0 to 2.1.22, 2.2.0 to 2.2.19, 3.0.0 to 3.0.23, and 3.11.0 to 3.11.9, when using 'dc' or 'rack' internode_encryption setting, allows both encrypted and unencrypted internode connections. A misconfigured node or a malicious user can use the unencrypted connection despite not being in the same rack or dc, and bypass mutual TLS requirement.
How severe is CVE-2020-17516?: CVE-2020-17516 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-17516 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-17516?: CVE-2020-17516 affects Apache Cassandra. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-17516?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-17516 published?: CVE-2020-17516 was published on 2021-02-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apache:cassandra:*:*:*:*:*:*:*:*

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