---
id: "CVE-2026-91332"
kind: "vulnerability"
aliases: ["CVE-2026-91332"]
title: "Java SE Networking: unauthenticated network flaw lets attackers alter some data"
severity: "medium"
cvss: 5.3
epss: 0.00282
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["graalvm", "java", "jvm", "runtime", "self-hosted"]
not_affected_if: ["no-java", "patched-release"]
published_at: "2026-10-20T22:20:35+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-2026-91332", "first_seen_at": "2026-10-23T21:57:26+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91332", "first_seen_at": "2026-10-25T12:38:52+00:00"}]
---

# Java SE Networking: unauthenticated network flaw lets attackers alter some data

A flaw in the Networking component of Oracle Java SE lets an unauthenticated attacker over the network change some data the Java application can access. The sources describe integrity impact only, with CVSS 5.3 and no confidentiality or availability loss.

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

## How to check

- Run `java -version` to see the installed Java SE release and compare it with the affected versions listed in the advisory.
- Check whether GraalVM for JDK or GraalVM Enterprise Edition is in use, since those builds are also listed.

## Fix

- Move Oracle Java SE to a patched release from Oracle's Critical Patch Update for the affected line: `8u503-perf` or later, `11.0.32.1` or later, `17.0.20.1` or later, `21.0.12.1` or later, `25.0.4.1` or later.
- Move GraalVM for JDK to `17.0.20.1` or `21.0.12.1`, and GraalVM Enterprise Edition to `21.3.19.1.1` or later.

## Timeline

- 2026-10-23T21:57:26+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91332
- 2026-10-25T12:38:52+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91332

## From the sources

Vulnerability in Oracle Java SE (component: Networking).  Supported versions that are affected are Oracle Java SE: 8u503-perf, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27; Oracle GraalVM for JDK: 17.0.20.1 and  21.0.12.1; Oracle GraalVM Enterprise Edition: 21.3.19.1.1. Easily exploitable 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 5.3 (Integrity impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N).

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