CVE-2026-91645 Oracle CVE debrief

Who should care

Defenders responsible for Oracle Essbase instances should assess exposure and prioritize remediation. This includes operators, platform administrators, vulnerability management teams, and security teams. They should verify affected versions and apply patches, monitor for unauthorized read access attempts, and assess exposure of Oracle Essbase instances.

Why it matters

CVE-2026-91645 is a medium-severity vulnerability in Oracle Essbase that allows unauthenticated attackers to read a subset of accessible data. Defenders should assess exposure, prioritize remediation, and verify the impact.

• Verify affected versions and apply patches
• Monitor for unauthorized read access attempts
• Assess exposure of Oracle Essbase instances

Technical summary

CVE-2026-91645 is a vulnerability in Oracle Essbase that allows unauthenticated attackers to read a subset of accessible data. The CVSS score is 5.3, with a vector of CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N. It affects Oracle Essbase version 21.8.3.0.0. Successful attacks can result in unauthorized read access to a subset of Oracle Essbase accessible data. The vulnerability is easily exploitable and allows unauthenticated attackers with network access via HTTP to compromise Oracle Essbase. Defenders should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.

Defensive priority

Remediation is recommended. Verify affected versions and apply patches.

Recommended defensive actions

• Assess exposure of Oracle Essbase instances
• Verify affected versions and apply patches
• Monitor for unauthorized read access attempts
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its CVSS score and vector. The official CVE Program record and NIST NVD detail page offer source-provided CVE metadata and vulnerability assessment. Defenders should verify affected versions and apply patches. The CVE record was published on 2026-10-20T22:21:04.663Z and has not been modified since then.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.