Quick answers
- Is CVE-2026-91659 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-91659 being exploited in the wild.
- How severe is CVE-2026-91659?
- High severity, with a CVSS score of 7.7, published 20 October 2026.
- Which products and versions are affected?
- Oracle Essbase 21.8.3.0.0.
- Is there a fix for CVE-2026-91659?
- 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-2026-91659 attacked?
- It is attacked over the network, in a hosted service.
- Am I affected by CVE-2026-91659?
- 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
An easily exploitable vulnerability in the Oracle Essbase Build component allows a low-privileged attacker with network access via HTTP to escalate privileges and access critical data. The vulnerability has a scope change impact, meaning attacks on Essbase can significantly compromise additional systems. No authentication bypass or user interaction is required; the attacker only needs low-privilege network access.
Affected products
- Oracle Essbase 21.8.3.0.0
Timeline
- 2026-10-20: disclosed