How severe is CVE-2018-18850?

CVE-2018-18850 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-18850 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 12% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-18850?

CVE-2018-18850 affects Octopus Octopus Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-18850?

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-2018-18850 published?

CVE-2018-18850 was published on 2018-10-31 and last updated on 2026-06-17.

CVE-2018-18850

CVE-2018-18850 is a high-severity vulnerability in Octopus Octopus Server with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 12% places it in the 96th percentile, indicating an elevated likelihood of exploitation.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 12% (96th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Octopus Octopus Server
Published: 2018-10-31
Last modified: 2026-06-17

Description

In Octopus Deploy 2018.8.0 through 2018.9.x before 2018.9.1, an authenticated user with permission to modify deployment processes could upload a maliciously crafted YAML configuration, potentially allowing for remote execution of arbitrary code, running in the same context as the Octopus Server (for self-hosted installations by default, SYSTEM).

Frequently asked questions

What is CVE-2018-18850?: In Octopus Deploy 2018.8.0 through 2018.9.x before 2018.9.1, an authenticated user with permission to modify deployment processes could upload a maliciously crafted YAML configuration, potentially allowing for remote execution of arbitrary code, running in the same context as the Octopus Server (for self-hosted installations by default, SYSTEM).
How severe is CVE-2018-18850?: CVE-2018-18850 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-18850 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 12% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-18850?: CVE-2018-18850 affects Octopus Octopus Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-18850?: 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-2018-18850 published?: CVE-2018-18850 was published on 2018-10-31 and last updated on 2026-06-17.

References

https://github.com/OctopusDeploy/Issues/issues/5042

Affected products (1)

cpe:2.3:a:octopus:octopus_server:*:*:*:*:*:*:*:*

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