Red Hat Security Advisory: OpenJDK 21.0.12.1 Security Update for Windows Builds
Affects Red Hat OpenJDK 21.0.12.1Source GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 3.7 Low.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 18% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 18 Aug 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, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition | Affected
| Fixed in– |
Mavencom.oracle.java/java-sepkg:maven/com.oracle.java/java-seOther threats | Affected
| Fixed in– |
Mavencom.oracle.graalvm/graalvm-jdkpkg:maven/com.oracle.graalvm/graalvm-jdkOther 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
Apply the OpenJDK 21.0.12.1 update for Windows provided by Red Hat, which replaces version 21.0.12 and includes the necessary security fixes. Ensure all previously released relevant errata are applied before updating. Follow Red Hat's official update instructions as detailed in their knowledge base article.
Description
Red Hat has released a security update for its OpenJDK 21 build for Windows, version 21.0.12.1, which replaces version 21.0.12. This update addresses multiple security issues including improvements in resource resolving, HTTP connections, and TLS server functionality. The update is rated as having a moderate security impact. Users are advised to apply this update after ensuring all previous relevant errata are installed.
References
- access.redhat.com/errata/RHSA-2026:55789 (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_21.0.12/index (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_55789.json (opens in a new tab)