CVE-2026-91334
Awaiting Analysis Awaiting Analysis - Queue

Heap-based Buffer Overflow in Oracle Java SE

Publication date: 2026-10-20

Last updated on: 2026-10-28

Assigner: Oracle

Description
Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: ImageIO). 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 read access to a subset of 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 3.7 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N).

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-10-20
Last Modified
2026-10-28
Generated
2026-11-10
AI Q&A
2026-10-21
EPSS Evaluated
2026-11-08
NVD
CVE-2026-91334
EUVD
EUVD-2026-106588

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-200 The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

This is a vulnerability in Oracle Java SE, Oracle GraalVM for JDK, and Oracle GraalVM Enterprise Edition affecting multiple versions. It allows an unauthenticated attacker with network access to read a subset of data accessible to these systems. The attack is difficult to exploit and requires network access via multiple protocols. The vulnerability exists in the ImageIO component and can be triggered through APIs, including web services supplying data to them.

Detection Guidance

This vulnerability is related to Oracle Java SE ImageIO component and requires checking installed Java versions. Use commands like 'java -version' to verify installed versions and compare against affected versions (8u503, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27). For GraalVM, check 'gu --version' or similar commands.

Impact Analysis

An attacker could exploit this to gain unauthorized read access to sensitive data processed by vulnerable Java applications. This includes data handled by Java Web Start applications or applets running in a sandbox. The impact is limited to confidentiality, meaning data could be viewed but not modified or deleted.

Compliance Impact

This vulnerability allows unauthorized read access to a subset of data, which could lead to exposure of sensitive information. For GDPR, this may result in violations of data confidentiality requirements. For HIPAA, it could compromise protected health information if accessed. However, the specific impact depends on the data processed by the affected Java applications.

Mitigation Strategies

Update affected Oracle Java SE, GraalVM for JDK, or GraalVM Enterprise Edition installations to the latest patched versions immediately. Disable Java Web Start applications and sandboxed Java applets if they are not required. Restrict network access to Java services where possible.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-91334. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart

Security Radar

News mentioning this vulnerability
Loading related security news...