---
id: "CVE-2026-91381"
kind: "vulnerability"
aliases: ["CVE-2026-91381"]
title: "Oracle Java SE 2D: unauthenticated network flaw lets attacker change some data"
severity: "low"
cvss: 3.7
epss: 0.00232
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["graalvm", "java", "oracle-java", "runtime", "self-hosted"]
not_affected_if: ["default-config", "no-untrusted-input"]
published_at: "2026-10-20T22:20:41+00:00"
first_seen_at: "2026-10-23T21:57:26+00:00"
updated_at: "2026-10-25T12:38:52+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91381", "first_seen_at": "2026-10-23T21:57:26+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91381", "first_seen_at": "2026-10-25T12:38:52+00:00"}]
---

# Oracle Java SE 2D: unauthenticated network flaw lets attacker change some data

A flaw in the 2D component of Oracle Java SE 8u503 and GraalVM Enterprise 21.3.19.1.1 lets an unauthenticated remote attacker modify some accessible data. Exploitation is hard and can be reached through a web service that feeds data to the affected APIs, or through sandboxed Java applets and Web Start apps that run untrusted code.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `java -version` and compare against the affected build `8u503` (or `8u503-perf`)
- For GraalVM Enterprise, check the version against `21.3.19.1.1`
- Look for Java web services or applets that pass untrusted input to the 2D (java.awt, java.awt.image) APIs

## Fix

- Move Oracle Java SE to the patched release listed in Oracle's April 2026 Critical Patch Update advisory (unknown exact version in sources)
- Move Oracle GraalVM Enterprise to a patched release (unknown in sources)

## Timeline

- 2026-10-23T21:57:26+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91381
- 2026-10-25T12:38:52+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91381

## From the sources

Vulnerability in the Oracle Java SE, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: 2D).  Supported versions that are affected are Oracle Java SE: 8u503 and  8u503-perf; Oracle GraalVM Enterprise Edition: 21.3.19.1.1. Difficult to exploit vulnerability allows unauthenticated attacker with network access via multiple protocols to compromise Oracle Java SE, Oracle GraalVM Enterprise Edition.  Successful attacks of this vulnerability can result in  unauthorized update, insert or delete access to some of Oracle Java SE, Oracle GraalVM Enterprise Edition 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).

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