---
id: "CVE-2026-87290"
kind: "vulnerability"
aliases: ["CVE-2026-87290"]
title: "Oracle Java SE: JAXP flaw lets unauthenticated network attackers read data"
severity: "medium"
cvss: 5.9
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["graalvm", "java", "jdk", "runtime", "self-hosted", "web-services"]
not_affected_if: ["default-config"]
published_at: "2026-10-20T22:20:05+00:00"
first_seen_at: "2026-10-23T21:57:25+00:00"
updated_at: "2026-10-25T04:08:23+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-87290", "first_seen_at": "2026-10-23T21:57:25+00:00"}]
---

# Oracle Java SE: JAXP flaw lets unauthenticated network attackers read data

A flaw in the JAXP XML component of Oracle Java SE and GraalVM lets an unauthenticated attacker over the network reach confidential data through APIs that a web service feeds with input. The CVSS score is 5.9 with high confidentiality impact and no integrity or availability impact.

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

## How to check

- Run `java -version` and compare the build with the affected releases: 8u503, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27, and GraalVM 17.0.20.1, 21.0.12.1, 21.3.19.1.1.
- Check whether a web service passes untrusted input into JAXP XML parsing APIs.

## Fix

- Move Oracle Java SE to a patched release from Oracle's July 2026 Critical Patch Update (the sources do not give exact fixed build numbers).
- Move Oracle GraalVM for JDK and GraalVM Enterprise Edition to a patched release from the same update.

## Timeline

- 2026-10-23T21:57:25+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-87290

## From the sources

Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: JAXP).  Supported versions that are affected are Oracle Java SE: 8u503, 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 network access via multiple protocols to compromise Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition.  Successful attacks of this vulnerability can result in  unauthorized access to critical data or complete access to all Oracle Java SE, Oracle GraalVM for JDK, 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 5.9 (Confidentiality impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N).

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_