CVE-2026-4881

In affected versions of Octopus Server, users with certain scoped permission sets could execute arbitrary scripts in an environment without possessing the required authorization.

Octopus Server incorrectly evaluates multiple scoped permission assignments, allowing a highly privileged user to obtain deployment permissions beyond those actually granted. This affects versions with the flawed permission evaluation logic.

In affected versions of Octopus Server, an authenticated user with permission to modify roles could bypass the protections preventing access abuse resulting in privilege escalation. It was possible for the built-in role to be weakened and the attacker's account added to a privileged team. This was achievable due to improper validation of unsafe equivalence in inputs.

In affected versions of Octopus Server, an authenticated user with permissions to edit an Environment or Project can set specifically crafted JSON content. Insecure deserialization of this content allows arbitrary code execution in the Octopus Server process.

In affected versions of Octopus Server, a user with permission to modify non built-in external feeds could exploit a path traversal flaw to overwrite arbitrary files on the server, potentially leading to remote code execution in some configurations.

In affected versions of Octopus Server, users with certain scoped permission sets could execute arbitrary scripts on a worker, including the built-in worker. Incorrect permission validation during script execution allowed the script to run without the user having the required authorization.

In affected versions of Octopus Server, sensitive variables may be printed in clear-text in the deployment variable snapshot under certain circumstances.

In affected versions of Octopus Server with certain access levels it was possible to embed a Cross-Site Scripting Payload via artifacts.