Unauthenticated Access Vulnerability in Oracle Database Server
CVE-2026-91479

6.5MEDIUM

Key Information:

Vendor

Oracle
Status
Oracle Database Server
Vendor
CVE Published:
20 October 2026

What is CVE-2026-91479?

A vulnerability exists in the RDBMS component of Oracle Database Server, affecting versions 23.4.0 through 23.26.3. An unauthenticated attacker with physical access to the communication segment where the RDBMS is hosted can exploit this vulnerability. Successful exploitation may allow the attacker to induce a denial of service condition by causing the RDBMS to hang or crash repeatedly. This poses a significant risk to the availability of database services and can disrupt operations.

Affected Version(s)

Oracle Database Server 23.4.0 <= 23.26.3

References

https://www.oracle.com/security-alerts/cpuoct2026.html
vendor-advisory

CVSS V3.1

Score:
6.5
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Adjacent Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.