CVE-2026-91642 Oracle CVE debrief

Who should care

Defenders responsible for Oracle Essbase deployments, particularly those with network access via HTTP, should assess exposure and prioritize verification and compensating controls.

Why it matters

CVE-2026-91642 is a high-severity vulnerability in Oracle Essbase 21.8.3.0.0 that allows unauthenticated attackers with network access via HTTP to compromise the system. Defenders should prioritize verifying exposure, assessing compensating controls, and monitoring for unauthorized data access and system modifications. Evidence from the CVE record and NVD entry supports these impacts, but further verification is needed to confirm affected versions and remediation steps.

• Potential unauthorized update, insert or delete access to some Oracle Essbase accessible data
• Potential unauthorized read access to a subset of Oracle Essbase accessible data
• Potential partial denial of service (partial DOS) of Oracle Essbase

Technical summary

The CVE-2026-91642 vulnerability in Oracle Essbase 21.8.3.0.0 allows unauthenticated attackers with network access via HTTP to compromise the system, potentially leading to unauthorized data access and partial denial of service. The CVSS 3.1 Base Score is 7.3, indicating a high severity. This vulnerability is in the Security component of Oracle Essbase. Successful attacks can result in unauthorized update, insert or delete access to some of Oracle Essbase accessible data as well as unauthorized read access to a subset of Oracle Essbase accessible data and unauthorized ability to cause a partial denial of service (partial DOS) of Oracle Essbase.

Defensive priority

Defenders should prioritize verifying exposure of Oracle Essbase 21.8.3.0.0 and assessing compensating controls, with a focus on network access via HTTP.

Recommended defensive actions

• Verify exposure of Oracle Essbase 21.8.3.0.0 and assess compensating controls
• Restrict network access to Oracle Essbase
• Monitor for unauthorized data access and system modifications
• Apply vendor patches or updates when available
• 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

Evidence notes

The CVE record and NVD entry provide details on the vulnerability in Oracle Essbase 21.8.3.0.0, allowing unauthenticated attackers with network access via HTTP to compromise the system, potentially leading to unauthorized data access and partial denial of service.

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.