How severe is CVE-2021-27017?

CVE-2021-27017 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-27017 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.

How do I fix CVE-2021-27017?

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

Does CVE-2021-27017 have an EU (EUVD) identifier?

Yes. CVE-2021-27017 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-13790.

When was CVE-2021-27017 published?

CVE-2021-27017 was published on 2025-02-07 and last updated on 2026-06-17.

CVE-2021-27017

CVE-2021-27017 is a medium-severity vulnerability with a CVSS 3.x base score of 6.6. 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-502.

Key facts

Severity: Medium (CVSS 3.x base score 6.6)
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-13790
Weakness: CWE-502
Published: 2025-02-07
Last modified: 2026-06-17

Description

Utilization of a module presented a security risk by allowing the deserialization of untrusted/user supplied data. This is resolved in the Puppet Agent 7.4.0 release.

Frequently asked questions

What is CVE-2021-27017?: Utilization of a module presented a security risk by allowing the deserialization of untrusted/user supplied data. This is resolved in the Puppet Agent 7.4.0 release.
How severe is CVE-2021-27017?: CVE-2021-27017 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-27017 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.
How do I fix CVE-2021-27017?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-27017 have an EU (EUVD) identifier?: Yes. CVE-2021-27017 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-13790.
When was CVE-2021-27017 published?: CVE-2021-27017 was published on 2025-02-07 and last updated on 2026-06-17.

References

https://www.puppet.com/security/cve/cve-2021-27017-deserialization-untrusted-data

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