How severe is CVE-2026-4881?

CVE-2026-4881 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-4881 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-4881?

CVE-2026-4881 affects Octopus Octopus Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-4881?

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

Does CVE-2026-4881 have an EU (EUVD) identifier?

Yes. CVE-2026-4881 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34227.

When was CVE-2026-4881 published?

CVE-2026-4881 was published on 2026-06-04 and last updated on 2026-06-30.

CVE-2026-4881

CVE-2026-4881 is a medium-severity vulnerability in Octopus Octopus Server with a CVSS 3.x base score of 6.5. 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-862.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 6.0
EPSS exploit prediction: 0% (11th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-34227
Weakness: CWE-862
Affected product: Octopus Octopus Server
Published: 2026-06-04
Last modified: 2026-06-30

Description

In affected versions of Octopus Server, permissions were not checked correctly resulting in any authenticated user being able to make server level changes using a certain API endpoint despite receiving an error.

Frequently asked questions

What is CVE-2026-4881?: In affected versions of Octopus Server, permissions were not checked correctly resulting in any authenticated user being able to make server level changes using a certain API endpoint despite receiving an error.
How severe is CVE-2026-4881?: CVE-2026-4881 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-4881 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-4881?: CVE-2026-4881 affects Octopus Octopus Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-4881?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-4881 have an EU (EUVD) identifier?: Yes. CVE-2026-4881 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-34227.
When was CVE-2026-4881 published?: CVE-2026-4881 was published on 2026-06-04 and last updated on 2026-06-30.

References

https://advisories.octopus.com/post/2026/sa2026-04

Affected products (1)

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

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