Quick answers
- Is CVE-2026-91394 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-91394 being exploited in the wild.
- How severe is CVE-2026-91394?
- Medium severity, with a CVSS score of 5.9, published 20 October 2026.
- Which products and versions are affected?
- Oracle Graalvm For Jdk 17.0.20.1, 21.0.12.1; Oracle Java SE 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27.
- Is there a fix for CVE-2026-91394?
- 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-2026-91394 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-91394?
- Check whether you run 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
A difficult-to-exploit information disclosure vulnerability exists in the Networking component of Oracle Java SE and GraalVM for JDK. An unauthenticated attacker with network access can exploit this via multiple protocols by supplying data to the affected Networking APIs, potentially through a web service or untrusted Java Web Start/applet code. Exploitation requires high attack complexity and results in confidentiality impact without integrity or availability compromise.
Affected products
- Oracle Java SE 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, 21.0.12.1
Timeline
- 2026-10-20: disclosed: Oracle Critical Patch Update October 2026