CVE-2026-91487: Medium severity Oracle Java SE vulnerability

Published Oct 20, 2026
·
Updated

Vulnerability in Oracle Java SE (component: Compiler). Supported versions that are affected are Oracle Java SE: 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. Successful attacks of this vulnerability can result in unauthorized update, insert or delete access to some of Oracle Java SE accessible data as well as unauthorized read access to a subset 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 4.8 (Confidentiality and Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N).

Affected Software

55 affected componentsFixes available
Oracle Java SE=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/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*
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*
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*
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*
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*
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*
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*
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/openjdk21 to a version that resolves this vulnerability.

    Fixed in 21.0.13.0.3_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 ubuntu/openjdk-lts to a version that resolves this vulnerability.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    Fixed in 25.0.5.0.3+1-1~26.04.1
  23. 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·10:23 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 exposed to this issue?

Affected supported releases are Oracle Java SE 8u503-perf, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, and 27; Oracle GraalVM for JDK 17.0.20.1 and 21.0.12.1; and Oracle GraalVM Enterprise Edition 21.3.19.1.1. Exploitation requires an application to supply attacker-controlled data to Compiler component APIs, for example through a web service.

2

Does exploitation require authentication, user interaction, or untrusted Java Web Start applications or applets?

No authentication or user interaction is required, but exploitation is rated difficult and requires network access through multiple protocols. The issue is exploitable without using untrusted Java Web Start applications or untrusted Java applets.

3

What could a successful attacker do?

A successful attacker could obtain unauthorized read access to a subset of accessible data and unauthorized update, insert, or delete access to some accessible data. The vulnerability does not have an availability impact in the supplied CVSS vector.

Company

Resources

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203