Quick answers
- Is CVE-2026-91656 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-91656 being exploited in the wild.
- How severe is CVE-2026-91656?
- Critical severity, with a CVSS score of 9.1, published 20 October 2026.
- Which products and versions are affected?
- Oracle Essbase 21.8.3.0.0.
- Is there a fix for CVE-2026-91656?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-91656 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-91656?
- Check whether you run Oracle Essbase 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
A network-accessible vulnerability in Oracle Essbase's Federated Partitions component allows low-privileged attackers to escalate privileges via HTTP without user interaction. Successful exploitation results in unauthorized access to critical data, data modification capabilities, and partial denial of service; the vulnerability has scope change, meaning it can affect systems beyond Essbase itself.
Affected products
- Oracle Essbase 21.8.3.0.0
Timeline
- 2026-10-20: disclosed