How severe is CVE-2021-20106?

CVE-2021-20106 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-20106 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20106?

CVE-2021-20106 affects Tenable Nessus. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20106?

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

When was CVE-2021-20106 published?

CVE-2021-20106 was published on 2021-07-21 and last updated on 2026-06-17.

CVE-2021-20106

CVE-2021-20106 is a medium-severity vulnerability in Tenable Nessus with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 8.5
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Tenable Nessus
Published: 2021-07-21
Last modified: 2026-06-17

Description

Nessus Agent versions 8.2.5 and earlier were found to contain a privilege escalation vulnerability which could allow a Nessus administrator user to upload a specially crafted file that could lead to gaining administrator privileges on the Nessus host.

Frequently asked questions

What is CVE-2021-20106?: Nessus Agent versions 8.2.5 and earlier were found to contain a privilege escalation vulnerability which could allow a Nessus administrator user to upload a specially crafted file that could lead to gaining administrator privileges on the Nessus host.
How severe is CVE-2021-20106?: CVE-2021-20106 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-20106 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20106?: CVE-2021-20106 affects Tenable Nessus. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20106?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-20106 published?: CVE-2021-20106 was published on 2021-07-21 and last updated on 2026-06-17.

References

https://www.tenable.com/security/tns-2021-13

Affected products (1)

cpe:2.3:a:tenable:nessus:*:*:*:*:*:*:*:*

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