# CVE-2026-91778: Octopus Deploy Server privilege escalation in script execution

Source: https://junglewise.ai/threats/cve-2026-91778-octopus-deploy-server-privilege-escalation-in-script-execution  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-15. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-91778 · Severity: info · CVSS 7.2 · Published 2026-09-15

Octopus Server is a deployment automation platform used to manage releases and configurations across distributed infrastructure. A flaw in permission validation allows users with limited access to execute arbitrary scripts on worker machines, including the built-in server worker, bypassing authorization controls that should restrict such actions. This could enable unauthorized users to compromise worker machines and potentially gain access to sensitive deployment data and infrastructure.

Technologies: [Octopus Deploy Octopus Server](https://junglewise.ai/threats/technologies/octopus-server). Vendors: [Octopus Deploy](https://junglewise.ai/threats/vendors/octopus-deploy).

## Quick answers

**Is CVE-2026-91778 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-91778 being exploited in the wild.

**How severe is CVE-2026-91778?** Informational severity, with a CVSS score of 7.2, published 15 September 2026.

**Which products and versions are affected?** Octopus Deploy Octopus Server All 2019.x, 2020.x, 2021.x, 2022.x, 2023.x, 2024.x, 2025.x; all 2026.1.x before 2026.1.11725; all 2026.2.x before 2026.2.13344; all 2026.3.x before 2026.3.15816.

**Is there a fix for CVE-2026-91778?** A patch was published on 2026-08-20. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-91778 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-91778?** Check whether you run Octopus Deploy Octopus Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is an authorization bypass in Octopus Server's script execution engine on workers. Users with certain scoped permission sets could execute arbitrary scripts without possessing the required authorisation due to incorrect permission validation logic. The vulnerability affects script execution on workers including the built-in Octopus Server worker, allowing network-accessible authenticated users to escalate privileges and run commands outside their intended scope. No public exploits are known at the time of advisory release. Patches are available for all affected major versions: 2026.1.11725, 2026.2.13344, and 2026.3.15816.

## Affected products

- Octopus Deploy Octopus Server All 2019.x, 2020.x, 2021.x, 2022.x, 2023.x, 2024.x, 2025.x; all 2026.1.x before 2026.1.11725; all 2026.2.x before 2026.2.13344; all 2026.3.x before 2026.3.15816

## Timeline

- 2026-09-15: disclosed
- 2026-08-20: patched

## References

- [https://advisories.octopus.com/post/2026/sa2026-08](https://advisories.octopus.com/post/2026/sa2026-08)

## Related threats

- [Octopus Server authorization bypass in LDAP identity editing](https://junglewise.ai/threats/cve-2026-124628-in-affected-versions-of-octopus-server-incorrect-validation-of)
- [Octopus Server LDAP identity injection leading to privilege escalation](https://junglewise.ai/threats/cve-2026-124627-in-affected-versions-of-octopus-server-incorrect-validation-of)
- [Octopus Server OIDC claim validation bypass](https://junglewise.ai/threats/cve-2026-116835-in-affected-versions-of-octopus-server-insufficient-validation)
- [Octopus Server incorrect authorization in project triggers](https://junglewise.ai/threats/cve-2026-93487-in-affected-versions-of-octopus-server-incorrect-validation-of)
- [Octopus Server privilege escalation in LDAP login editing](https://junglewise.ai/threats/cve-2026-105948-in-affected-versions-of-octopus-server-incorrect-validation-of)