CVE-2026-4747 — FreeBSD kgssapi.ko RPCSEC_GSS Stack Buffer Overflow
Summary
This security write-up analyzes CVE-2026-4747, a stack-based overflow in FreeBSD kgssapi.ko RPCSEC_GSS that can enable remote kernel code execution over NFS when a valid Kerberos context is presented. It details the vulnerability, the patch that fixes it, and the complex exploitation considerations, including Kerberos token handling and multi-round payload delivery, making it a valuable resource for security researchers and incident responders.