# CVE-2026-91778: Missing authorization in Octopus Server

> Users with scoped permissions can execute arbitrary scripts on workers due to incorrect permission validation, leading to code execution and privilege escalation.

- **Severity:** High 7.2 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Sep 2026
- **Updated:** 15 Sep 2026
- **Also known as:** GHSA-9wjw-f37c-vj83

## What is CVE-2026-91778?

CVE-2026-91778 is a high-severity missing authorization vulnerability in Octopus Server, published on 15 Sep 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, users with certain scoped permission sets could execute arbitrary scripts on a worker (including the Octopus Server built-in worker). Incorrect permission validation during script execution would allow the script to execute without the user possessing the required authorisation.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-91778?


## How do I fix CVE-2026-91778?

No fix has been published for CVE-2026-91778 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-91778 being exploited?

There is no known exploitation of CVE-2026-91778 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-91778 and fix it if it is affected.

What it is: CVE-2026-91778 is a high-severity missing authorization vulnerability in Octopus Server, published on 15 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-91778 in the wild and no public exploit code.

Affected product: Octopus Server. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-91778/ (Markdown: https://insights.sbomify.com/CVE-2026-91778/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-91778
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-91778
- OSV: https://osv.dev/vulnerability/CVE-2026-91778

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-91778/
Summaries are generated and may contain mistakes; the official description above is the record.