Red Hat Security Advisory: OpenJDK 21.0.10 Security Update for Windows Builds
Affects Red Hat OpenJDK 21.0.10Source GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 4.8 Medium.
Data as of 30 Oct 2026, 06:16 UTC
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 20 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Oracle CorporationOracle Java SE | Affected
| Fixed in– |
| Oracle CorporationOracle GraalVM for JDK | Affected
| Fixed in– |
| Oracle CorporationOracle GraalVM Enterprise Edition | Affected
| Fixed in– |
Mavencom.oracle/java-sepkg:maven/com.oracle/java-seOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has released OpenJDK 21.0.10 for Windows as a security update that fixes the identified vulnerabilities. Users should apply this update to replace version 21.0.9 after ensuring all previously released errata relevant to their system have been applied. Detailed update instructions are available from Red Hat's official documentation. No additional mitigation actions are indicated beyond applying this update.
Description
Red Hat has released an important security update for the OpenJDK 21 build for Windows, version 21.0.10, which replaces version 21.0.9. This update addresses multiple security vulnerabilities related to JMX connections, URI handling, HTTP server request processing, and certificate checking. The update includes fixes for CVE-2026-21925, CVE-2026-21932, CVE-2026-21933, and CVE-2026-21945. The advisory recommends applying this update after ensuring all previous errata are applied.
References
- access.redhat.com/errata/RHSA-2026:0900 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- docs.redhat.com/en/documentation/red_hat_build_of_openjdk/21/html/release_notes_for_red_hat_build_of_openjdk_21.0.10/index (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_0900.json (opens in a new tab)