CVE-2026-68127
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk7th percentile - higher than 7% of all known CVEs
Summary
In the Linux kernel ILA module, after calling pskb_may_pull(), the IPv6 header pointer may become stale, leading to use-after-free. The fix reloads the pointer after each pskb_may_pull().
Risk Assessment
A remote attacker can send an IPv6 packet that triggers a use-after-free in the kernel, leading to a crash or potential code execution.
Recommendation
Apply the Linux kernel update with the fix for CVE-2026-68127. Restrict ILA route configuration to trusted administrators.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: ila: reload IPv6 header after pskb_may_pull in checksum adjust ila_csum_adjust_transport() caches ip6h = ipv6_hdr(skb) before calling pskb_may_pull(). On a non-linear skb whose transport header sits in a page fragment, pskb_may_pull() can call __pskb_pull_tail() / pskb_expand_head() and free the old skb head, leaving ip6h dangling; the following get_csum_diff(ip6h, p) then reads freed memory. ila_update_ipv6_locator() uses ip6h (and the iaddr derived from it) again after the csum-adjust call and additionally writes the new locator through that pointer. Impact: a remote IPv6 packet routed through a configured ILA csum-adjust-transport route or receive-side mapping triggers a slab-use-after-free in ila_update_ipv6_locator() (KASAN). The route or mapping requires CAP_NET_ADMIN to configure, but trigger packets are unauthenticated once it exists. Reload ip6h after each pskb_may_pull() in ila_csum_adjust_transport() before the csum-diff read. In ila_update_ipv6_locator() only the ILA_CSUM_ADJUST_TRANSPORT case pulls the skb, so reload ip6h and iaddr in that case alone before the destination-address write; the neutral-map modes never pull and keep their cached pointers.