How severe is CVE-2020-26161?

CVE-2020-26161 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-26161 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-26161?

CVE-2020-26161 affects Octopus Octopus Deploy. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-26161?

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

When was CVE-2020-26161 published?

CVE-2020-26161 was published on 2020-10-26 and last updated on 2026-06-17.

CVE-2020-26161

CVE-2020-26161 is a medium-severity vulnerability in Octopus Octopus Deploy with a CVSS 3.x base score of 6.1. 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-601.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 5.8
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-601
Affected product: Octopus Octopus Deploy
Published: 2020-10-26
Last modified: 2026-06-17

Description

In Octopus Deploy through 2020.4.2, an attacker could redirect users to an external site via a modified HTTP Host header.

Frequently asked questions

What is CVE-2020-26161?: In Octopus Deploy through 2020.4.2, an attacker could redirect users to an external site via a modified HTTP Host header.
How severe is CVE-2020-26161?: CVE-2020-26161 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-26161 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-26161?: CVE-2020-26161 affects Octopus Octopus Deploy. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-26161?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-26161 published?: CVE-2020-26161 was published on 2020-10-26 and last updated on 2026-06-17.

References

Affected products (1)

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

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