How severe is CVE-2021-20077?

CVE-2021-20077 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-20077 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20077?

CVE-2021-20077 affects Tenable Nessus Agent. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20077?

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

When was CVE-2021-20077 published?

CVE-2021-20077 was published on 2021-03-19 and last updated on 2026-06-17.

CVE-2021-20077

CVE-2021-20077 is a medium-severity vulnerability in Tenable Nessus Agent with a CVSS 3.x base score of 6.7. 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 6.7)
CVSS v2: 7.2
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Tenable Nessus Agent
Published: 2021-03-19
Last modified: 2026-06-17

Description

Nessus Agent versions 7.2.0 through 8.2.2 were found to inadvertently capture the IAM role security token on the local host during initial linking of the Nessus Agent when installed on an Amazon EC2 instance. This could allow a privileged attacker to obtain the token.

Frequently asked questions

What is CVE-2021-20077?: Nessus Agent versions 7.2.0 through 8.2.2 were found to inadvertently capture the IAM role security token on the local host during initial linking of the Nessus Agent when installed on an Amazon EC2 instance. This could allow a privileged attacker to obtain the token.
How severe is CVE-2021-20077?: CVE-2021-20077 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-20077 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20077?: CVE-2021-20077 affects Tenable Nessus Agent. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20077?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-20077 published?: CVE-2021-20077 was published on 2021-03-19 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:tenable:nessus_agent:*:*:*:*:*:*:*:*

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