# CVE-2026-91659: Oracle Essbase privilege escalation via HTTP in Build component

Source: https://junglewise.ai/threats/cve-2026-91659-vulnerability-in-oracle-essbase-component-build-the-supported  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-20. Updated: 2026-10-20  
License: CC BY 4.0 with a link back

CVE-2026-91659 · Severity: high · CVSS 7.7 · Published 2026-10-20

Oracle Essbase is a cloud-based analytics and planning platform used by enterprises to manage critical financial and operational data. A vulnerability in the Build component allows a low-privileged network attacker to gain unauthorized access to sensitive data without requiring interaction from users, affecting the confidentiality of all data within Essbase and potentially other connected systems.

Technologies: [Oracle Essbase](https://junglewise.ai/threats/technologies/essbase). Vendors: [Oracle](https://junglewise.ai/threats/vendors/oracle).

## 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

## References

- [https://www.oracle.com/security-alerts/cpuoct2026.html](https://www.oracle.com/security-alerts/cpuoct2026.html)

## Related threats

- [Oracle Essbase unauthenticated remote code execution](https://junglewise.ai/threats/cve-2026-91665-vulnerability-in-oracle-essbase-component-security-the-supported)
- [Oracle Essbase denial of service in Security component](https://junglewise.ai/threats/cve-2026-91664-vulnerability-in-oracle-essbase-component-security-the-supported)
- [Oracle Essbase privilege escalation in Security component](https://junglewise.ai/threats/cve-2026-91663-vulnerability-in-oracle-essbase-component-security-the-supported)
- [Oracle Essbase privilege escalation in Java Based Agent](https://junglewise.ai/threats/cve-2026-91662-vulnerability-in-oracle-essbase-component-java-based-agent-the)
- [Oracle Essbase authentication bypass in security component](https://junglewise.ai/threats/cve-2026-91661-vulnerability-in-oracle-essbase-component-security-the-supported)