CVE-2026-9589 Unblu Spark Authorization Bypass in Configuration Cascade Operations
- Exploited in the wild
- Not known
- Fix
- None listed
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.
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.
Sources
Also known as GHSA-m9mc-chm4-qcpm.