CVE-2026-72442

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

netfilter: flowtable: fix and simplify IP6IP6 tunnel handling

Fix nf_flow_ip6_tunnel_proto() to use pskb_may_pull() instead of

skb_header_pointer() to ensure the outer IPv6 header is in the skb

headroom, which is required for subsequent packet processing. Move

ctx->offset update inside the IPPROTO_IPV6 conditional block since it

should only be adjusted when an IP6IP6 tunnel is actually detected.

Simplify the rx path by removing ipv6_skip_exthdr() and checking

ip6h->nexthdr directly, as the flowtable fast path only handles simple

IP6IP6 encapsulation without extension headers.

Drop the tunnel encapsulation limit destination option support from the

tx path to match, since the rx path no longer handles extension headers.

Remove the encap_limit parameter from nf_flow_offload_ipv6_forward(),

nf_flow_tunnel_ip6ip6_push() and nf_flow_tunnel_v6_push(), along with

the ipv6_tel_txoption struct and related headroom/MTU adjustme

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References