This advisory covers security fixes in the Linux kernel packages for Red Hat Enterprise Linux 9.6 Extended Update Support. The fixed vulnerabilities include CVE-2025-21826, which addresses a netfilter nf_tables issue rejecting mismatching sum of field_len with set key length; CVE-2026-64017, which fixes blk-mq cached request handling; CVE-2026-64368, which corrects slab zeroing behavior when only red zoning is enabled; and CVE-2026-64564, which prevents freeing the ASCONF's own transport in SCTP DEL-IP processing. The advisory also includes bug fixes and enhancements for Intel ice drivers. Red Hat recommends treating all kernel errata as security-relevant and advises prompt application of this update.

The vulnerabilities fixed by this update affect core kernel components, which could impact system stability and security. The netfilter nf_tables issue could allow improper packet filtering behavior. The blk-mq cached request fix addresses potential request handling errors. The slab zeroing fix corrects memory zeroing behavior that could affect memory safety. The SCTP fix prevents improper freeing of transport structures that could lead to memory corruption. Red Hat rates the security impact as Important, indicating these issues could affect system security if unpatched.

A security update for the kernel packages is available and should be applied promptly. Systems must be rebooted after installing the update to ensure the fixes take effect. Red Hat strongly recommends not delaying this update as it improves the overall security posture. Detailed update instructions are available at https://access.redhat.com/articles/11258. No additional mitigations are specified beyond applying the official update and rebooting.