CVE-2026-31665

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> netfilter: nft_ct: fix use-after-free in timeout object destroy<br /> <br /> nft_ct_timeout_obj_destroy() frees the timeout object with kfree()<br /> immediately after nf_ct_untimeout(), without waiting for an RCU grace<br /> period. Concurrent packet processing on other CPUs may still hold<br /> RCU-protected references to the timeout object obtained via<br /> rcu_dereference() in nf_ct_timeout_data().<br /> <br /> Add an rcu_head to struct nf_ct_timeout and use kfree_rcu() to defer<br /> freeing until after an RCU grace period, matching the approach already<br /> used in nfnetlink_cttimeout.c.<br /> <br /> KASAN report:<br /> BUG: KASAN: slab-use-after-free in nf_conntrack_tcp_packet+0x1381/0x29d0<br /> Read of size 4 at addr ffff8881035fe19c by task exploit/80<br /> <br /> Call Trace:<br /> nf_conntrack_tcp_packet+0x1381/0x29d0<br /> nf_conntrack_in+0x612/0x8b0<br /> nf_hook_slow+0x70/0x100<br /> __ip_local_out+0x1b2/0x210<br /> tcp_sendmsg_locked+0x722/0x1580<br /> __sys_sendto+0x2d8/0x320<br /> <br /> Allocated by task 75:<br /> nft_ct_timeout_obj_init+0xf6/0x290<br /> nft_obj_init+0x107/0x1b0<br /> nf_tables_newobj+0x680/0x9c0<br /> nfnetlink_rcv_batch+0xc29/0xe00<br /> <br /> Freed by task 26:<br /> nft_obj_destroy+0x3f/0xa0<br /> nf_tables_trans_destroy_work+0x51c/0x5c0<br /> process_one_work+0x2c4/0x5a0