CVE-2026-4881 Missing authorization in Octopus Server

What is CVE-2026-4881?

CVE-2026-4881 is a medium-severity missing authorization vulnerability in Octopus Octopus Server, published on 4 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official 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.

Weakness: CWE-862

Which versions are affected by CVE-2026-4881?

It affects 1 product.

Products include Octopus Octopus Server.

How do I fix CVE-2026-4881?

No fix has been published for CVE-2026-4881 yet. Limit exposure of the affected software until one is available.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2026-4881 being exploited?

There is no known exploitation of CVE-2026-4881 in the wild and no public exploit code.

Other vulnerabilities in Octopus Octopus Server

• CVE-2022-2572 Auth bypass in Octopus Server Critical 9.8
• CVE-2022-2778 Security feature bypass in Octopus Server Critical 9.8
• CVE-2018-11320 Information disclosure in n/a Critical 9.8
• CVE-2022-2782 Auth bypass in Octopus Server Critical 9.1
• CVE-2024-2975 Race condition in Octopus Server High 8.8

All Octopus Octopus Server vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-hw3f-962q-p4vj.