CVE-2026-91640 Oracle CVE debrief

Who should care

Defenders responsible for Oracle Essbase deployments, particularly those with version 21.8.3.0.0, should assess their exposure and potential impact of this vulnerability. They should prioritize verifying exposure of Oracle Essbase version 21.8.3.0.0 and assessing the impact of potential unauthorized read access to Oracle Essbase data. Defenders should also implement network access controls to limit access to Oracle Essbase and monitor Oracle Essbase logs

Why it matters

Defenders should prioritize verifying exposure of Oracle Essbase version 21.8.3.0.0 and assessing the impact of potential unauthorized read access to Oracle Essbase data. This vulnerability allows low-privileged attackers with network access via HTTP to compromise Oracle Essbase, potentially impacting additional products.

• Verification of Oracle Essbase version 21.8.3.0.0 exposure is required to determine potential impact.
• Potential unauthorized read access to Oracle Essbase data may occur if the vulnerability is exploited.
• Network access controls and monitoring of Oracle Essbase logs are necessary to detect and prevent potential security incidents.

Technical summary

The vulnerability in Oracle Essbase (component: Security) is easily exploitable and allows low-privileged attackers with network access via HTTP to compromise Oracle Essbase. Successful attacks can result in unauthorized read access to a subset of Oracle Essbase accessible data. The CVSS 3.1 Base Score is 5.0 (Confidentiality impacts). The vulnerability affects Oracle Essbase version 21.8.3.0.0 and has a CVSS vector of (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N). Defenders should prioritize verifying exposure of Oracle Essbase version 21.8.3.0.0 and assessing the impact of potential unauthorized read access to Oracle Essbase data.

Defensive priority

Defenders should prioritize verifying exposure of Oracle Essbase version 21.8.3.0.0 and assessing the impact of potential unauthorized read access to Oracle Essbase data.

Recommended defensive actions

• Verify the exposure of Oracle Essbase version 21.8.3.0.0 in your environment.
• Assess the potential impact of unauthorized read access to Oracle Essbase data.
• Implement network access controls to limit access to Oracle Essbase.
• Monitor Oracle Essbase logs for potential security incidents.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• 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 of 5.0 and vector (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N). The vulnerability affects Oracle Essbase version 21.8.3.0.0 and allows low-privileged attackers with network access via HTTP to compromise Oracle Essbase. Successful attacks can result in unauthorized read access to a subset of Oracle Essbase accessible data. The CVE record was published on 2026-10-20T22:21:04.073Z and has not been modified since then. The NVD entry provides a CV

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.