CVE-2026-91658

CRITICAL

Summary

generated automatically from NVD data

CVE-2026-91658 affects the Security component of Oracle Essbase, specifically version 21.8.3.0.0. A low-privileged attacker with network access over HTTP can exploit this easily, and a successful attack could result in takeover of Oracle Essbase. Because the scope changes, other products may also be significantly impacted. The flaw has a CVSS v3.1 score of 9.9 (CRITICAL), with high confidentiality, integrity and availability impacts.

NVD description

Vulnerability in Oracle Essbase (component: Security). The supported version that is affected is 21.8.3.0.0. Easily exploitable vulnerability allows low privileged attacker with network access via HTTP to compromise Oracle Essbase. While the vulnerability is in Oracle Essbase, attacks may significantly impact additional products (scope change). Successful attacks of this vulnerability can result in takeover of Oracle Essbase. CVSS 3.1 Base Score 9.9 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H).

EPSS · FIRST.org

0.29%probability of exploitation in the next 30 days

Higher than 19% of scored CVEs

EPSS (Exploit Prediction Scoring System) estimates, from observed exploitation activity, how likely a CVE is to be exploited in the next 30 days. It complements CVSS, which measures severity, not likelihood. Score of 2026-10-21, recomputed daily by FIRST.org.

In-depth analysis on cveo.tech

We've published a detailed analysis of this CVE — exploitation, IOCs and mitigation.