How severe is CVE-2018-6517?

CVE-2018-6517 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-2018-6517 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-6517?

CVE-2018-6517 affects Puppet Chloride. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-6517?

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-2018-6517 published?

CVE-2018-6517 was published on 2019-03-21 and last updated on 2026-06-17.

CVE-2018-6517

CVE-2018-6517 is a high-severity vulnerability in Puppet Chloride 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: 5.0
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Puppet Chloride
Published: 2019-03-21
Last modified: 2026-06-17

Description

Prior to version 0.3.0, chloride's use of net-ssh resulted in host fingerprints for previously unknown hosts getting added to the user's known_hosts file without confirmation. In version 0.3.0 this is updated so that the user's known_hosts file is not updated by chloride.

Frequently asked questions

What is CVE-2018-6517?: Prior to version 0.3.0, chloride's use of net-ssh resulted in host fingerprints for previously unknown hosts getting added to the user's known_hosts file without confirmation. In version 0.3.0 this is updated so that the user's known_hosts file is not updated by chloride.
How severe is CVE-2018-6517?: CVE-2018-6517 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-2018-6517 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-6517?: CVE-2018-6517 affects Puppet Chloride. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-6517?: 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-2018-6517 published?: CVE-2018-6517 was published on 2019-03-21 and last updated on 2026-06-17.

References

https://puppet.com/security/cve/CVE-2018-6517

Affected products (1)

cpe:2.3:a:puppet:chloride:*:*:*:*:*:*:*:*

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