---
id: "CVE-2026-91375"
kind: "vulnerability"
aliases: ["CVE-2026-91375"]
title: "Oracle Java SE Libraries: local attacker can modify data via untrusted input"
severity: "medium"
cvss: 4.7
epss: 0.00092
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["graalvm", "java", "oracle-jdk", "runtime", "self-hosted"]
not_affected_if: ["other-jdk-vendor", "patched-build"]
published_at: "2026-10-20T22:20:40+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-2026-91375", "first_seen_at": "2026-10-23T21:57:26+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91375", "first_seen_at": "2026-10-25T12:38:52+00:00"}]
---

# Oracle Java SE Libraries: local attacker can modify data via untrusted input

A flaw in the Libraries component of Oracle Java SE lets an attacker with logon to the host modify data when a person takes an action such as running untrusted code. The CVSS 3.1 score is 4.7 with integrity impact only.

_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 releases: 8u503-perf, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27.
- Check whether GraalVM for JDK 17.0.20.1 or 21.0.12.1, or GraalVM Enterprise Edition 21.3.19.1.1, is installed.

## Fix

- Move Oracle Java SE to a patched release from Oracle's July 2026 Critical Patch Update (exact fixed versions unknown from the sources).
- Move Oracle GraalVM to a patched release (exact fixed versions unknown from the sources).

## Timeline

- 2026-10-23T21:57:26+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91375
- 2026-10-25T12:38:52+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91375

## From the sources

Vulnerability in Oracle Java SE (component: Libraries).  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. Difficult to exploit vulnerability allows unauthenticated attacker with logon to the infrastructure where Oracle Java SE executes to compromise Oracle Java SE.  Successful attacks require human interaction from a person other than the attacker. Successful attacks of this vulnerability can result in  unauthorized creation, deletion or modification access to critical data or all 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 4.7 (Integrity impacts).  CVSS Vector: (CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N).

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