CVE-2026-91451: Medium severity Oracle Java SE vulnerability

Published Oct 20, 2026
·
Updated

Vulnerability in 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; Oracle GraalVM for JDK: 17.0.20.1 and 21.0.12.1; Oracle GraalVM Enterprise Edition: 21.3.19.1.1. Easily exploitable vulnerability allows unauthenticated attacker with network access via multiple protocols to compromise Oracle Java SE. Successful attacks of this vulnerability can result in unauthorized update, insert or delete access to some of Oracle Java SE accessible data. Note: This vulnerability can only be exploited by supplying data to APIs in the specified Component without using Untrusted Java Web Start applications or Untrusted Java applets, such as through a web service. CVSS 3.1 Base Score 5.3 (Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N).

Affected Software

57 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
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/openjdk21<21.0.13.0.3_p1-r0
21.0.13.0.3_p1-r0
alpine/openjdk21<21.0.13.0.3_p1-r0
21.0.13.0.3_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/openjdk21 to a version that resolves this vulnerability.

    Fixed in 21.0.13.0.3_p1-r0
  8. Upgrade

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

    Fixed in 25.0.5.0.3_p1-r0
  9. Upgrade

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

    Fixed in 11.0.33+9-1
  10. 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
  11. 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
  12. 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
  13. Upgrade

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

    Fixed in 27.0.1.0.3+1-1
  14. Upgrade

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

    Fixed in 8u512-ga-1
  15. Upgrade

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    Fixed in 8u512-b09~us1-0ubuntu1~26.04.1
  32. 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·09:26 PM
Data Sourced
via MITRE·09:26 PM
DescriptionSeverity
Data Sourced
via OSV·10:20 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·10:20 PM
DescriptionSeverityWeakness
Data Sourced
via Red Hat·11:12 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

Which deployments are most exposed?

Deployments that accept network-supplied data through APIs in the Networking component are exposed, including scenarios such as a web service. The issue is exploitable through multiple protocols by an unauthenticated attacker with network access.

2

Are Java Web Start applications or Java applets required for exploitation?

No. The vulnerability is exploitable by supplying data to the affected component's APIs without using untrusted Java Web Start applications or untrusted Java applets.

3

Which releases should be checked in the environment?

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

4

What can a successful attacker do?

Successful exploitation can allow unauthorized update, insertion, or deletion of some data accessible to the affected Oracle Java SE instance. The stated CVSS impact is limited to integrity; no confidentiality or availability impact is listed.

Company

Resources

Contact

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