# CVE-2026-9589: Unblu Spark Authorization Bypass in Configuration Cascade Operations


- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:H/SA:H`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 20 Oct 2026
- **Updated:** 20 Oct 2026
- **Also known as:** GHSA-m9mc-chm4-qcpm

## What is CVE-2026-9589?

CVE-2026-9589 is a critical vulnerability in Unblu Spark, published on 20 Oct 2026. 

### Official description

Missing authorization in the configuration cascade operations of the Collaboration Server in Unblu inc. Unblu Spark 7.0 through 8.36.1-hotfix.0, on on-premises and cloud deployments, allows an authenticated remote attacker to read and change configuration properties of entities they aren't authorized to access, including other users, other accounts and, in Unblu Cloud, other customers' accounts, via configuration read and write operations that target those entities.

The Collaboration Server doesn't check whether the user reading or changing configuration has access to the entity the configuration belongs to. With certain non-default configuration validation settings, a registered user can additionally write configuration properties they aren't allowed to edit, in any scope.

Exploitation requires an authenticated session but no user interaction.

Weakness: CWE-862 (Missing Authorization), CWE-639 (Authorization Bypass Through User-Controlled Key)

## Which versions are affected by CVE-2026-9589?


## How do I fix CVE-2026-9589?

No fix has been published for CVE-2026-9589 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-9589 being exploited?

There is no known exploitation of CVE-2026-9589 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-9589 and fix it if it is affected.

What it is: CVE-2026-9589 is a critical vulnerability in Unblu Spark, published on 20 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-9589 in the wild and no public exploit code.

Affected product: Unblu Spark. 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-2026-9589/ (Markdown: https://insights.sbomify.com/CVE-2026-9589/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-9589
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-9589
- OSV: https://osv.dev/vulnerability/CVE-2026-9589

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-9589/
Summaries are generated and may contain mistakes; the official description above is the record.