Linux Kernel CVE-2026-99284: Local Privilege Escalation to Root and the Required Fix

Zero Day Initiative published an advisory for CVE-2026-99284 in Linux Kernel. An ownership-management flaw during zero-copy can lead to local privilege escalation; organizations should identify the running kernel and compare it with vendor update information. Read the Zero Day Initiative advisory.

Overview and technical details

Linux Kernel is the Linux operating system kernel, managing hardware resources and providing core system services. CVE-2026-99284 involves incorrect ownership management in the skb_zerocopy function.

Affected systems

The advisory concerns Linux Kernel, but the available information does not identify affected or fixed branches or versions. Administrators should compare the kernel version on each system with vendor update information to determine its patch status.

Mechanism and impact

During zero-copy, the shared ownership state of packet fragments is not propagated in the skb_zerocopy function. An attacker must be able to execute code with low privileges on the target system; successful exploitation can enable privilege escalation and arbitrary code execution as root.

System checks

1. Record the running kernel version, then compare it with vendor update information to determine patch status.
   Copy commands

   uname -r

Remediation and mitigation

1. Prioritize identifying Linux machines running affected kernels.
2. Update Linux Kernel to a Linux-issued update containing the fix. The related fix is published in commit 79dc34beb1fdb3da79753e51e15c68591a2561fe.

References

• CVE-2026-99284 advisory – Zero Day Initiative
• Fix – Linux Kernel commit