What is CVE-2026-87398?

CVE-2026-87398 is a high-severity vulnerability in Oracle Corporation Outside In Technology, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-10-20.

How severe is CVE-2026-87398?

High severity. CVSS v3 base score is 7.5 out of 10.

Resource exhaustion in Oracle Corporation Outside In Technology

CVE-2026-87398

Vulnerability in the Oracle Outside In Technology product of Oracle Fusion Middleware (component: Outside In Core). The supported version that is affected is 8.5.8. Easily exploitable vulnerability allows unauthenticated attacker with network access via HTTP to compromise Oracle Outside In Technology. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of Oracle Outside In Technology. CVSS 3.1 Base Score 7.5 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

Vulnerability class: DoS (Denial of Service)

Published 2026-10-20 · last modified 2026-10-21.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Oracle Corporation Outside In Technology — versions 8.5.8

Weakness classification (CWE)

CWE-400 — Uncontrolled Resource Consumption

References

www.oracle.com/security-alerts/cpuoct2026.html (vendor-advisory)

Frequently asked questions

What is CVE-2026-87398?: CVE-2026-87398 is a high-severity vulnerability in Oracle Corporation Outside In Technology, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-10-20.
How severe is CVE-2026-87398?: High severity. CVSS v3 base score is 7.5 out of 10.