This Red Hat security advisory covers the OpenJDK 11 ELS update to version 11.0.28 for portable Linux builds, which includes security and bug fixes. The update addresses five distinct vulnerabilities affecting the Java Runtime Environment and Software Development Kit, including improvements to glyph rendering, TLS protocol support, scripting capabilities, and HTTP client header handling. The advisory references five CVEs, each corresponding to specific security issues resolved in this release. Red Hat classifies the update as Important and recommends applying it after prior errata are installed. The advisory does not provide CVSS scores but directs users to the CVE pages for detailed severity information.

The update mitigates multiple security vulnerabilities in OpenJDK 11 ELS that could affect the integrity and security of Java applications running on affected Red Hat Enterprise Linux versions. The vulnerabilities relate to graphical rendering, TLS protocol handling, scripting support, and HTTP client header processing, which could potentially lead to security issues if left unpatched. Red Hat rates the overall impact as Important, indicating a high but not critical severity level. There are no known exploits in the wild at the time of this advisory.

A security update to OpenJDK 11 ELS version 11.0.28 is available from Red Hat and should be applied to affected systems. Before applying this update, ensure all previously released errata relevant to your system have been installed. Detailed instructions for applying the update are available in the Red Hat knowledge base article linked in the advisory. No additional mitigation steps are indicated beyond applying this official update.