{"uuid": "16a56278-1d8d-43dd-a27a-73f03d8c9ad5", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "2a075640-a300-48a4-bb44-bc6130783b9b", "vulnerability": "CVE-2025-21707", "type": "seen", "source": "https://t.me/cvedetector/18996", "content": "{\n  \"Source\": \"CVE FEED\",\n  \"Title\": \"CVE-2025-21707 - Linux MPTCP Uninitialized Bitfield Vulnerability\", \n  \"Content\": \"CVE ID : CVE-2025-21707 \nPublished : Feb. 27, 2025, 2:15 a.m. | 50\u00a0minutes ago \nDescription : In the Linux kernel, the following vulnerability has been resolved:  \n  \nmptcp: consolidate suboption status  \n  \nMPTCP maintains the received sub-options status is the bitmask carrying  \nthe received suboptions and in several bitfields carrying per suboption  \nadditional info.  \n  \nZeroing the bitmask before parsing is not enough to ensure a consistent  \nstatus, and the MPTCP code has to additionally clear some bitfiled  \ndepending on the actually parsed suboption.  \n  \nThe above schema is fragile, and syzbot managed to trigger a path where  \na relevant bitfield is not cleared/initialized:  \n  \n  BUG: KMSAN: uninit-value in __mptcp_expand_seq net/mptcp/options.c:1030 [inline]  \n  BUG: KMSAN: uninit-value in mptcp_expand_seq net/mptcp/protocol.h:864 [inline]  \n  BUG: KMSAN: uninit-value in ack_update_msk net/mptcp/options.c:1060 [inline]  \n  BUG: KMSAN: uninit-value in mptcp_incoming_options+0x2036/0x3d30 net/mptcp/options.c:1209  \n   __mptcp_expand_seq net/mptcp/options.c:1030 [inline]  \n   mptcp_expand_seq net/mptcp/protocol.h:864 [inline]  \n   ack_update_msk net/mptcp/options.c:1060 [inline]  \n   mptcp_incoming_options+0x2036/0x3d30 net/mptcp/options.c:1209  \n   tcp_data_queue+0xb4/0x7be0 net/ipv4/tcp_input.c:5233  \n   tcp_rcv_established+0x1061/0x2510 net/ipv4/tcp_input.c:6264  \n   tcp_v4_do_rcv+0x7f3/0x11a0 net/ipv4/tcp_ipv4.c:1916  \n   tcp_v4_rcv+0x51df/0x5750 net/ipv4/tcp_ipv4.c:2351  \n   ip_protocol_deliver_rcu+0x2a3/0x13d0 net/ipv4/ip_input.c:205  \n   ip_local_deliver_finish+0x336/0x500 net/ipv4/ip_input.c:233  \n   NF_HOOK include/linux/netfilter.h:314 [inline]  \n   ip_local_deliver+0x21f/0x490 net/ipv4/ip_input.c:254  \n   dst_input include/net/dst.h:460 [inline]  \n   ip_rcv_finish+0x4a2/0x520 net/ipv4/ip_input.c:447  \n   NF_HOOK include/linux/netfilter.h:314 [inline]  \n   ip_rcv+0xcd/0x380 net/ipv4/ip_input.c:567  \n   __netif_receive_skb_one_core net/core/dev.c:5704 [inline]  \n   __netif_receive_skb+0x319/0xa00 net/core/dev.c:5817  \n   process_backlog+0x4ad/0xa50 net/core/dev.c:6149  \n   __napi_poll+0xe7/0x980 net/core/dev.c:6902  \n   napi_poll net/core/dev.c:6971 [inline]  \n   net_rx_action+0xa5a/0x19b0 net/core/dev.c:7093  \n   handle_softirqs+0x1a0/0x7c0 kernel/softirq.c:561  \n   __do_softirq+0x14/0x1a kernel/softirq.c:595  \n   do_softirq+0x9a/0x100 kernel/softirq.c:462  \n   __local_bh_enable_ip+0x9f/0xb0 kernel/softirq.c:389  \n   local_bh_enable include/linux/bottom_half.h:33 [inline]  \n   rcu_read_unlock_bh include/linux/rcupdate.h:919 [inline]  \n   __dev_queue_xmit+0x2758/0x57d0 net/core/dev.c:4493  \n   dev_queue_xmit include/linux/netdevice.h:3168 [inline]  \n   neigh_hh_output include/net/neighbour.h:523 [inline]  \n   neigh_output include/net/neighbour.h:537 [inline]  \n   ip_finish_output2+0x187c/0x1b70 net/ipv4/ip_output.c:236  \n   __ip_finish_output+0x287/0x810  \n   ip_finish_output+0x4b/0x600 net/ipv4/ip_output.c:324  \n   NF_HOOK_COND include/linux/netfilter.h:303 [inline]  \n   ip_output+0x15f/0x3f0 net/ipv4/ip_output.c:434  \n   dst_output include/net/dst.h:450 [inline]  \n   ip_local_out net/ipv4/ip_output.c:130 [inline]  \n   __ip_queue_xmit+0x1f2a/0x20d0 net/ipv4/ip_output.c:536  \n   ip_queue_xmit+0x60/0x80 net/ipv4/ip_output.c:550  \n   __tcp_transmit_skb+0x3cea/0x4900 net/ipv4/tcp_output.c:1468  \n   tcp_transmit_skb net/ipv4/tcp_output.c:1486 [inline]  \n   tcp_write_xmit+0x3b90/0x9070 net/ipv4/tcp_output.c:2829  \n   __tcp_push_pending_frames+0xc4/0x380 net/ipv4/tcp_output.c:3012  \n   tcp_send_fin+0x9f6/0xf50 net/ipv4/tcp_output.c:3618  \n   __tcp_close+0x140c/0x1550 net/ipv4/tcp.c:3130  \n   __mptcp_close_ssk+0x74e/0x16f0 net/mptcp/protocol.c:2496  \n   mptcp_close_ssk+0x26b/0x2c0 net/mptcp/protocol.c:2550  \n   mptcp_pm_nl_rm_addr_or_subflow+0x635/0xd10 net/mptcp/pm_netlink.c:889  \n   mptcp_pm_nl_rm_subflow_received net/mptcp/pm_netlink.c:924 [i[...]", "creation_timestamp": "2025-02-27T04:31:10.000000Z"}