CVE-2026-80840

CVE-2026-80840 is a slab-out-of-bounds write in the Linux kernel IPv6 Segment Routing (seg6) code. When End.DX4 or End.DT4 decapsulates an inner IPv4 packet via decap_and_validate(), the skb retains stale IP6CB data that overlaps with IPCB fields. A crafted outer Destination Options header sets o...