---
id: "CVE-2026-83374"
kind: "vulnerability"
aliases: ["CVE-2026-83374"]
title: "Oracle Java SE: a hard-to-exploit flaw lets remote users alter data"
severity: "medium"
cvss: 5.9
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["graalvm", "java", "oracle-java-se", "runtime", "self-hosted", "web-services"]
not_affected_if: ["no-java-runtime", "no-network-exposed-java-apis"]
published_at: "2026-10-20T22:19:53+00:00"
first_seen_at: "2026-10-23T21:57:25+00:00"
updated_at: "2026-10-25T04:08:25+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-83374", "first_seen_at": "2026-10-23T21:57:25+00:00"}]
---

# Oracle Java SE: a hard-to-exploit flaw lets remote users alter data

Oracle Java SE, GraalVM for JDK and GraalVM Enterprise Edition contain a flaw in the Security component that an unauthenticated attacker over the network can use to create, delete or modify data the Java application can reach. Exploitation is hard, and the advisory notes it can happen through a web service that passes data to the affected APIs, and through sandboxed Java applets or Web Start apps running 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 releases: 8u503, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27.
- For GraalVM, check the GraalVM for JDK releases 17.0.20.1 and 21.0.12.1, and Enterprise Edition 21.3.19.1.1.
- Look for sandboxed applets or Java Web Start use on client machines (unknown whether the sources list specific paths).

## Fix

- Oracle Java SE: move to a patched release from the Oracle Critical Patch Update for the affected line (the sources do not list the fixed version numbers).
- Oracle GraalVM for JDK and Enterprise Edition: update to a fixed build from Oracle (fixed version unknown in the sources).

## Timeline

- 2026-10-23T21:57:25+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-83374

## From the sources

Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: Security).  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 creation, deletion or modification access to critical data or 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 (Integrity impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/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_