# CVE-2026-91410: Oracle Java SE partial denial of service in Libraries component

Source: https://junglewise.ai/threats/cve-2026-91410-vulnerability-in-oracle-java-se-component-libraries-supported  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-20. Updated: 2026-10-20  
License: CC BY 4.0 with a link back

CVE-2026-91410 · Severity: medium · CVSS 5.3 · Published 2026-10-20

Oracle Java SE contains a vulnerability in its Libraries component that allows unauthenticated attackers to cause partial service disruption through network access. The flaw can be exploited via APIs exposed through web services or by loading untrusted code in Java Web Start applications and applets. Affected deployments will experience temporary unavailability, impacting business applications relying on Java.

Technologies: [Oracle GraalVM Enterprise Edition](https://junglewise.ai/threats/technologies/graalvm-enterprise-edition), [Oracle Graalvm For Jdk](https://junglewise.ai/threats/technologies/graalvm-for-jdk), [Oracle Java SE](https://junglewise.ai/threats/technologies/java-se). Vendors: [Oracle](https://junglewise.ai/threats/vendors/oracle).

## Quick answers

**Is CVE-2026-91410 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-91410 being exploited in the wild.

**How severe is CVE-2026-91410?** Medium severity, with a CVSS score of 5.3, published 20 October 2026.

**Which products and versions are affected?** Oracle GraalVM Enterprise Edition 21.3.19.1.1; Oracle Graalvm For Jdk 17.0.20.1, 21.0.12.1; Oracle Java SE 8u503, 8u503-perf, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1.

**Is there a fix for CVE-2026-91410?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-91410 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-91410?** Check whether you run Oracle GraalVM Enterprise Edition, Oracle Graalvm For Jdk or Oracle Java SE at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An easily exploitable vulnerability in Oracle Java SE's Libraries component allows unauthenticated network attackers to trigger a partial denial of service. The vulnerability is reachable through multiple network protocols and APIs; exploitation is also possible by supplying malicious data to affected APIs via web services or by executing untrusted code in sandboxed Java environments. Successful exploitation causes partial availability impact with no confidentiality or integrity breach.

## Affected products

- Oracle Java SE 8u503, 8u503-perf, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1
- Oracle GraalVM for JDK 17.0.20.1, 21.0.12.1
- Oracle GraalVM Enterprise Edition 21.3.19.1.1

## Timeline

- 2026-10-20: disclosed

## References

- [https://www.oracle.com/security-alerts/cpuoct2026.html](https://www.oracle.com/security-alerts/cpuoct2026.html)

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