Karp Linux Kernel Level Arp Hijacking Spoofing Utility Apr 2026

If you find an unexpected module, rmmod karp – but a real attacker will hide it via rootkit techniques. kArp demonstrates a simple truth: moving attacks from user space to kernel space increases reliability and evades kill‑‑9 . Red teams can use this to persist on compromised routers or jump hosts. Defenders must move beyond process monitoring to kernel integrity checks (e.g., tripwire for modules, IMA, or eBPF-based LSM hooks).

Enter : a proof-of-concept Linux Kernel Module (LKM) that performs ARP hijacking directly from NF_INET_POST_ROUTING and NF_INET_LOCAL_IN Netfilter hooks. By staying in kernel space, kArp achieves microsecond-level response times and deterministic spoofing. kArp Linux Kernel Level ARP Hijacking Spoofing Utility

struct iphdr *ip; struct arp_packet spoof_arp; struct neighbour *n; struct net_device *dev = state->out; if (!skb) return NF_ACCEPT; If you find an unexpected module, rmmod karp

static unsigned int karphook_post(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) Defenders must move beyond process monitoring to kernel