How severe is CVE-2021-27018?

CVE-2021-27018 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 none, integrity high, and availability none.

Is CVE-2021-27018 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27018?

CVE-2021-27018 affects Puppet Remediate. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27018?

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-2021-27018 published?

CVE-2021-27018 was published on 2021-08-30 and last updated on 2026-06-17.

CVE-2021-27018

CVE-2021-27018 is a high-severity vulnerability in Puppet Remediate 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-295.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Puppet Remediate
Published: 2021-08-30
Last modified: 2026-06-17

Description

The mechanism which performs certificate validation was discovered to have a flaw that resulted in certificates signed by an internal certificate authority to not be properly validated. This issue only affects clients that are configured to utilize Tenable.sc as the vulnerability data source.

Frequently asked questions

What is CVE-2021-27018?: The mechanism which performs certificate validation was discovered to have a flaw that resulted in certificates signed by an internal certificate authority to not be properly validated. This issue only affects clients that are configured to utilize Tenable.sc as the vulnerability data source.
How severe is CVE-2021-27018?: CVE-2021-27018 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 none, integrity high, and availability none.
Is CVE-2021-27018 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27018?: CVE-2021-27018 affects Puppet Remediate. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27018?: 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-2021-27018 published?: CVE-2021-27018 was published on 2021-08-30 and last updated on 2026-06-17.

References

https://puppet.com/security/cve/CVE-2021-27018

Affected products (1)

cpe:2.3:a:puppet:remediate:*:*:*:*:*:*:*:*

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