Vulnerability details
CVE-2026-9589
Unblu Spark Authorization Bypass in Configuration Cascade Operations
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.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 9.3Critical | 4.0 | CVEProject cvelistV5 (CNA) (NCSC.ch) | 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 |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| Unblu inc. | Unblu Spark | 7.0 ≤ v < 8.37.0 | CVEProject cvelistV5 (CNA) |
References and advisories
1- https://docs.unblu.com/latest/security-bulletins/#UBL-2026-002 vendor-advisory
Details
- Published
- 2026-10-20
- Last updated
- 2026-10-20
- State
- Published
- Assigner (CNA)
- NCSC.ch
- Kolun priority
- 21 · Low
Exploit prediction (EPSS)
SSVC assessment (CISA)
- Automatable
- No
- Exploitation
- None
- Technical impact
- Total
Weaknesses (CWE)
- CWE-862Missing Authorization
- CWE-639Authorization Bypass Through User-Controlled Key