In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix use-after-free in ip6finishoutput2()
ip6finishoutput2() caches a pointer to the IPv6 destination address (daddr) before invoking lwtunnelxmit(). The LWT-BPF transmit path or other encapsulation operations within lwtunnelxmit() can reallocate the skb head, freeing the memory that daddr points to. When lwtunnelxmit() returns LWTUNNELXMIT_CONTINUE, the function continues to use the stale daddr pointer to compute the nexthop and to look up or create the neighbour entry. This results in a use-after-free read, which can leak sensitive kernel data, pollute the neighbour table with arbitrary values, misdirect traffic, or crash the system.
Fix this by re-fetching the IPv6 header and the destination address pointer after lwtunnelxmit() returns LWTUNNELXMIT_CONTINUE, ensuring that the subsequent nexthop computation and neighbour lookup operate on valid memory.
{
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80792.json",
"cna_assigner": "Linux"
}