CVE-2026-43093: Linux Kernel

High severity, CVSS 7.8. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: xsk: tighten UMEM headroom validation to account for tailroom and min frame The current headroom validation in xdp_umem_reg() could leave us with insufficient space dedicated to even receive minimum-sized ethernet frame. Furthermore if multi-buffer would come to play then skb_shared_info stored at the end of XSK frame would be corrupted. HW typically works with 128-aligned sizes so let us provide this value as bare minimum. Multi-buffer setting is known later in the configuration process so besides accounting for 128 bytes, let us also take care of tailroom space upfront.

Affected products

• Linux Linux Kernel: from 4.19.118, before 4.20 (fixed in 4.20); from 5.4.35, before 5.5 (fixed in 5.5); from 5.6.7, before 5.7 (fixed in 5.7); from 5.7.1, before 6.6.136 (fixed in 6.6.136); from 6.7, before 6.12.83 (fixed in 6.12.83); from 6.13, before 6.18.24 (fixed in 6.18.24); …

Published 2026-05-06. Last modified 2026-06-17.