Oracle Java SE Security Component Vulnerability, Versions 21.0.12.1/25.0.4.1/27
CVE-2026-91333 Published on October 20, 2026

Vulnerability in Oracle Java SE (component: Security). Supported versions that are affected are Oracle Java SE: 21.0.12.1, 25.0.4.1 and 27. Difficult to exploit vulnerability allows unauthenticated attacker with network access via multiple protocols to compromise Oracle Java SE. Successful attacks of this vulnerability can result in unauthorized update, insert or delete access to some of Oracle Java SE accessible data. Note: This vulnerability can be exploited by using APIs in the specified Component, e.g., through a web service which supplies data to the APIs. This vulnerability also applies to Java deployments, typically in clients running sandboxed Java Web Start applications or sandboxed Java applets, that load and run untrusted code (e.g., code that comes from the internet) and rely on the Java sandbox for security. CVSS 3.1 Base Score 3.7 (Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N).

Vendor Advisory NVD

Vulnerability Analysis

CVE-2026-91333 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, with no impact on integrity, and no impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
HIGH
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
NONE
Integrity Impact:
LOW
Availability Impact:
NONE

Weakness Type

What is a Marshaling, Unmarshaling Vulnerability?

The application deserializes untrusted data without sufficiently verifying that the resulting data will be valid.

CVE-2026-91333 has been classified to as a Marshaling, Unmarshaling vulnerability or weakness.


Products Associated with CVE-2026-91333

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Affected Versions

Oracle Corporation Oracle Java SE: