How severe is CVE-2020-27155?

CVE-2020-27155 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-2020-27155 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-27155?

CVE-2020-27155 affects Octopus Octopus Deploy. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-27155?

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-2020-27155 published?

CVE-2020-27155 was published on 2020-10-22 and last updated on 2026-06-17.

CVE-2020-27155

CVE-2020-27155 is a high-severity vulnerability in Octopus Octopus Deploy 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.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Octopus Octopus Deploy
Published: 2020-10-22
Last modified: 2026-06-17

Description

An issue was discovered in Octopus Deploy through 2020.4.4. If enabled, the websocket endpoint may allow an untrusted tentacle host to present itself as a trusted one.

Frequently asked questions

What is CVE-2020-27155?: An issue was discovered in Octopus Deploy through 2020.4.4. If enabled, the websocket endpoint may allow an untrusted tentacle host to present itself as a trusted one.
How severe is CVE-2020-27155?: CVE-2020-27155 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-2020-27155 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27155?: CVE-2020-27155 affects Octopus Octopus Deploy. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-27155?: 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-2020-27155 published?: CVE-2020-27155 was published on 2020-10-22 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:octopus:octopus_deploy:*:*:*:*:*:*:*:*

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