# CVE-2026-91660: Oracle Essbase denial of service in Security component

Source: https://junglewise.ai/threats/cve-2026-91660-vulnerability-in-oracle-essbase-component-security-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-2026-91660 · Severity: medium · CVSS 4.3 · Published 2026-10-20

Oracle Essbase is a business analytics and planning platform used to manage corporate financial data and forecasts. A flaw in the Security component allows an attacker with low-level network access to partially disrupt the service, causing partial outages. An attacker with valid credentials can trigger this denial of service remotely over HTTP.

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

## Quick answers

**Is CVE-2026-91660 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-91660 being exploited in the wild.

**How severe is CVE-2026-91660?** Medium severity, with a CVSS score of 4.3, published 20 October 2026.

**Which products and versions are affected?** Oracle Essbase 21.8.3.0.0.

**Is there a fix for CVE-2026-91660?** 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-2026-91660 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-91660?** 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

The vulnerability is an easily exploitable denial of service in Oracle Essbase's Security component, accessible via HTTP to low-privileged users. An authenticated attacker with network access can trigger a partial denial of service affecting availability. A fix status has not been publicly disclosed in the available advisory material.

## 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)