CVE-2026-91398: Medium severity Oracle Java SE vulnerability

Published Oct 20, 2026
·
Updated

Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: Networking). 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 SOCKS5 to compromise Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition. While the vulnerability is in Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition, attacks may significantly impact additional products (scope change). 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 6.8 (Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N).

Affected Software

55 affected componentsFixes available
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, =21.0.12.1
Oracle GraalVM Enterprise Edition=21.3.19.1.1
debian/openjdk-17<17.0.21+9-1~deb12u1
17.0.21+9-1~deb12u1
debian/openjdk-21<21.0.13+9-1~deb13u2
21.0.13+9-1~deb13u2
debian/openjdk-21<21.0.13+9-1
21.0.13+9-1
debian/openjdk-25<25.0.5+8-1~deb13u1
25.0.5+8-1~deb13u1
debian/openjdk-25<25.0.5+8-1
25.0.5+8-1
debian/openjdk-27*
alpine/openjdk17<17.0.21.0.3_p1-r0
17.0.21.0.3_p1-r0
alpine/openjdk17<17.0.21.0.3_p1-r0
17.0.21.0.3_p1-r0
alpine/openjdk25<25.0.5.0.3_p1-r0
25.0.5.0.3_p1-r0
alpine/openjdk25<25.0.5.0.3_p1-r0
25.0.5.0.3_p1-r0
debian/openjdk-11
11.0.33+9-1
debian/openjdk-17<=17.0.19+10-1~deb12u2
17.0.21+9-1~deb12u117.0.21.0.3+1-1
debian/openjdk-21<=21.0.12.1+1-1~deb13u1
21.0.13+9-1~deb13u221.0.13.0.3+1-1
debian/openjdk-25<=25.0.3+9-2~deb13u1
25.0.5+8-1~deb13u125.0.5+8-125.0.5.0.3+1-1
debian/openjdk-27<=27~34ea-1
27.0.1.0.3+1-1
debian/openjdk-8
8u512-ga-1
ubuntu/openjdk-8<8u512-b09~us1-0ubuntu1~16.04.1
8u512-b09~us1-0ubuntu1~16.04.1
ubuntu/openjdk-9*
ubuntu/openjdk-lts<11.0.33+9-1ubuntu1~18.04.1
11.0.33+9-1ubuntu1~18.04.1
ubuntu/openjdk-17*
ubuntu/openjdk-8<8u512-b09~us1-0ubuntu1~18.04.1
8u512-b09~us1-0ubuntu1~18.04.1
ubuntu/openjdk-lts<11.0.33+9-1ubuntu1~20.04.1
11.0.33+9-1ubuntu1~20.04.1
ubuntu/openjdk-13*
ubuntu/openjdk-16*
ubuntu/openjdk-17*
ubuntu/openjdk-21*
ubuntu/openjdk-8<8u512-b09~us1-0ubuntu1~20.04.1
8u512-b09~us1-0ubuntu1~20.04.1
ubuntu/openjdk-17*
ubuntu/openjdk-21*
ubuntu/openjdk-25<25.0.5.0.3+1-1~22.04.1
25.0.5.0.3+1-1~22.04.1
ubuntu/openjdk-8<8u512-b09~us1-0ubuntu1~22.04.1
8u512-b09~us1-0ubuntu1~22.04.1
ubuntu/openjdk-lts<11.0.33+9-1ubuntu1~22.04.1
11.0.33+9-1ubuntu1~22.04.1
ubuntu/openjdk-17*
ubuntu/openjdk-21*
ubuntu/openjdk-25<25.0.5.0.3+1-1~24.04.1
25.0.5.0.3+1-1~24.04.1
ubuntu/openjdk-8<8u512-b09~us1-0ubuntu1~24.04.1
8u512-b09~us1-0ubuntu1~24.04.1
ubuntu/openjdk-lts<11.0.33+9-1ubuntu1~24.04.1
11.0.33+9-1ubuntu1~24.04.1
ubuntu/openjdk-17*
ubuntu/openjdk-17-crac*
ubuntu/openjdk-21*
ubuntu/openjdk-21-crac*
ubuntu/openjdk-25<25.0.5.0.3+1-1~26.10.1
25.0.5.0.3+1-1~26.10.1
ubuntu/openjdk-27<27.0.1.0.3+1-1~26.10.1
27.0.1.0.3+1-1~26.10.1
ubuntu/openjdk-8<8u512-b09~us1-0ubuntu1~26.10.1
8u512-b09~us1-0ubuntu1~26.10.1
ubuntu/openjdk-lts<11.0.33+9-1ubuntu1~26.10.1
11.0.33+9-1ubuntu1~26.10.1
ubuntu/openjdk-17*
ubuntu/openjdk-17-crac*
ubuntu/openjdk-21*
ubuntu/openjdk-21-crac*
ubuntu/openjdk-25<25.0.5.0.3+1-1~26.04.1
25.0.5.0.3+1-1~26.04.1
ubuntu/openjdk-8<8u512-b09~us1-0ubuntu1~26.04.1
8u512-b09~us1-0ubuntu1~26.04.1
ubuntu/openjdk-lts<11.0.33+9-1ubuntu1~26.04.1
11.0.33+9-1ubuntu1~26.04.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/openjdk-17 to a version that resolves this vulnerability.

    Fixed in 17.0.21+9-1~deb12u1
  2. Upgrade

    Upgrade debian/openjdk-21 to a version that resolves this vulnerability.

    Fixed in 21.0.13+9-1~deb13u2
  3. Upgrade

    Upgrade debian/openjdk-21 to a version that resolves this vulnerability.

    Fixed in 21.0.13+9-1
  4. Upgrade

    Upgrade debian/openjdk-25 to a version that resolves this vulnerability.

    Fixed in 25.0.5+8-1~deb13u1
  5. Upgrade

    Upgrade debian/openjdk-25 to a version that resolves this vulnerability.

    Fixed in 25.0.5+8-1
  6. Upgrade

    Upgrade alpine/openjdk17 to a version that resolves this vulnerability.

    Fixed in 17.0.21.0.3_p1-r0
  7. Upgrade

    Upgrade alpine/openjdk25 to a version that resolves this vulnerability.

    Fixed in 25.0.5.0.3_p1-r0
  8. Upgrade

    Upgrade debian/openjdk-11 to a version that resolves this vulnerability.

    Fixed in 11.0.33+9-1
  9. Upgrade

    Upgrade debian/openjdk-17 to a version that resolves this vulnerability.

    Fixed in 17.0.21+9-1~deb12u1Fixed in 17.0.21.0.3+1-1
  10. Upgrade

    Upgrade debian/openjdk-21 to a version that resolves this vulnerability.

    Fixed in 21.0.13+9-1~deb13u2Fixed in 21.0.13.0.3+1-1
  11. Upgrade

    Upgrade debian/openjdk-25 to a version that resolves this vulnerability.

    Fixed in 25.0.5+8-1~deb13u1Fixed in 25.0.5+8-1Fixed in 25.0.5.0.3+1-1
  12. Upgrade

    Upgrade debian/openjdk-27 to a version that resolves this vulnerability.

    Fixed in 27.0.1.0.3+1-1
  13. Upgrade

    Upgrade debian/openjdk-8 to a version that resolves this vulnerability.

    Fixed in 8u512-ga-1
  14. Upgrade

    Upgrade ubuntu/openjdk-8 to a version that resolves this vulnerability.

    Fixed in 8u512-b09~us1-0ubuntu1~16.04.1
  15. Upgrade

    Upgrade ubuntu/openjdk-lts to a version that resolves this vulnerability.

    Fixed in 11.0.33+9-1ubuntu1~18.04.1
  16. Upgrade

    Upgrade ubuntu/openjdk-8 to a version that resolves this vulnerability.

    Fixed in 8u512-b09~us1-0ubuntu1~18.04.1
  17. Upgrade

    Upgrade ubuntu/openjdk-lts to a version that resolves this vulnerability.

    Fixed in 11.0.33+9-1ubuntu1~20.04.1
  18. Upgrade

    Upgrade ubuntu/openjdk-8 to a version that resolves this vulnerability.

    Fixed in 8u512-b09~us1-0ubuntu1~20.04.1
  19. Upgrade

    Upgrade ubuntu/openjdk-25 to a version that resolves this vulnerability.

    Fixed in 25.0.5.0.3+1-1~22.04.1
  20. Upgrade

    Upgrade ubuntu/openjdk-8 to a version that resolves this vulnerability.

    Fixed in 8u512-b09~us1-0ubuntu1~22.04.1
  21. Upgrade

    Upgrade ubuntu/openjdk-lts to a version that resolves this vulnerability.

    Fixed in 11.0.33+9-1ubuntu1~22.04.1
  22. Upgrade

    Upgrade ubuntu/openjdk-25 to a version that resolves this vulnerability.

    Fixed in 25.0.5.0.3+1-1~24.04.1
  23. Upgrade

    Upgrade ubuntu/openjdk-8 to a version that resolves this vulnerability.

    Fixed in 8u512-b09~us1-0ubuntu1~24.04.1
  24. Upgrade

    Upgrade ubuntu/openjdk-lts to a version that resolves this vulnerability.

    Fixed in 11.0.33+9-1ubuntu1~24.04.1
  25. Upgrade

    Upgrade ubuntu/openjdk-25 to a version that resolves this vulnerability.

    Fixed in 25.0.5.0.3+1-1~26.10.1
  26. Upgrade

    Upgrade ubuntu/openjdk-27 to a version that resolves this vulnerability.

    Fixed in 27.0.1.0.3+1-1~26.10.1
  27. Upgrade

    Upgrade ubuntu/openjdk-8 to a version that resolves this vulnerability.

    Fixed in 8u512-b09~us1-0ubuntu1~26.10.1
  28. Upgrade

    Upgrade ubuntu/openjdk-lts to a version that resolves this vulnerability.

    Fixed in 11.0.33+9-1ubuntu1~26.10.1
  29. Upgrade

    Upgrade ubuntu/openjdk-25 to a version that resolves this vulnerability.

    Fixed in 25.0.5.0.3+1-1~26.04.1
  30. Upgrade

    Upgrade ubuntu/openjdk-8 to a version that resolves this vulnerability.

    Fixed in 8u512-b09~us1-0ubuntu1~26.04.1
  31. Upgrade

    Upgrade ubuntu/openjdk-lts to a version that resolves this vulnerability.

    Fixed in 11.0.33+9-1ubuntu1~26.04.1

Event History

Oct 20, 2026
CVE Published
via MITRE·09:25 PM
Data Sourced
via MITRE·09:25 PM
DescriptionSeverity
Data Sourced
via OSV·10:20 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·10:20 PM
DescriptionSeverityWeakness
Oct 21, 2026
Data Sourced
via Red Hat·12:25 AM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

Who is exposed to this vulnerability?

Affected deployments include the listed Oracle Java SE, Oracle GraalVM for JDK, and Oracle GraalVM Enterprise Edition versions where an attacker can reach the vulnerable networking functionality through SOCKS5. It can also affect Java deployments in clients running sandboxed Java Web Start applications or sandboxed Java applets.

2

What does an attacker need to exploit it?

The attacker does not need authentication or user interaction, but does need network access via SOCKS5. Exploitation is described as difficult and can occur through use of the affected component's APIs, including a web service that supplies data to those APIs.

3

What could happen if exploitation succeeds?

A successful attack can allow unauthorized creation, deletion, or modification of critical data or of all data accessible to the affected Java or GraalVM deployment. The scope change indicates that impacts may significantly extend to additional products.

Company

Resources

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