{"schema_version":"1.7.2","id":"OESA-2026-1949","modified":"2026-04-17T13:01:43Z","published":"2026-04-17T13:01:43Z","upstream":["CVE-2025-68291"],"summary":"kernel security update","details":"The Linux Kernel, the operating system core itself.\r\n\r\nSecurity Fix(es):\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().\n\nsyzbot reported divide-by-zero in __tcp_select_window() by\nMPTCP socket. [0]\n\nWe had a similar issue for the bare TCP and fixed in commit\n499350a5a6e7 ("tcp: initialize rcv_mss to TCP_MIN_MSS instead\nof 0").\n\nLet's apply the same fix to mptcp_do_fastclose().\n\n[0]:\nOops: divide error: 0000 [#1] SMP KASAN PTI\nCPU: 0 UID: 0 PID: 6068 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025\nRIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv4/tcp_output.c:3336\nCode: ff ff ff 44 89 f1 d3 e0 89 c1 f7 d1 41 01 cc 41 21 c4 e9 a9 00 00 00 e8 ca 49 01 f8 e9 9c 00 00 00 e8 c0 49 01 f8 44 89 e0 99 <f7> 7c 24 1c 41 29 d4 48 bb 00 00 00 00 00 fc ff df e9 80 00 00 00\nRSP: 0018:ffffc90003017640 EFLAGS: 00010293\nRAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88807b469e40\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000\nRBP: ffffc90003017730 R08: ffff888033268143 R09: 1ffff1100664d028\nR10: dffffc0000000000 R11: ffffed100664d029 R12: 0000000000000000\nR13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000\nFS:  000055557faa0500(0000) GS:ffff888126135000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007f64a1912ff8 CR3: 0000000072122000 CR4: 00000000003526f0\nCall Trace:\n <TASK>\n tcp_select_window net/ipv4/tcp_output.c:281 [inline]\n __tcp_transmit_skb+0xbc7/0x3aa0 net/ipv4/tcp_output.c:1568\n tcp_transmit_skb net/ipv4/tcp_output.c:1649 [inline]\n tcp_send_active_reset+0x2d1/0x5b0 net/ipv4/tcp_output.c:3836\n mptcp_do_fastclose+0x27e/0x380 net/mptcp/protocol.c:2793\n mptcp_disconnect+0x238/0x710 net/mptcp/protocol.c:3253\n mptcp_sendmsg_fastopen+0x2f8/0x580 net/mptcp/protocol.c:1776\n mptcp_sendmsg+0x1774/0x1980 net/mptcp/protocol.c:1855\n sock_sendmsg_nosec net/socket.c:727 [inline]\n __sock_sendmsg+0xe5/0x270 net/socket.c:742\n __sys_sendto+0x3bd/0x520 net/socket.c:2244\n __do_sys_sendto net/socket.c:2251 [inline]\n __se_sys_sendto net/socket.c:2247 [inline]\n __x64_sys_sendto+0xde/0x100 net/socket.c:2247\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7f66e998f749\nCode: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007ffff9acedb8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c\nRAX: ffffffffffffffda RBX: 00007f66e9be5fa0 RCX: 00007f66e998f749\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003\nRBP: 00007ffff9acee10 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001\nR13: 00007f66e9be5fa0 R14: 00007f66e9be5fa0 R15: 0000000000000006\n </TASK>(CVE-2025-68291)","affected":[{"package":{"ecosystem":"openEuler:24.03-LTS-SP3","name":"kernel","purl":"pkg:rpm/openEuler/kernel&distro=openEuler-24.03-LTS-SP3"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.0-145.0.3.134.oe2403sp3"}]}],"ecosystem_specific":{"aarch64":["bpftool-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","bpftool-debuginfo-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","kernel-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","kernel-debuginfo-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","kernel-debugsource-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","kernel-devel-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","kernel-extra-modules-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","kernel-headers-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","kernel-source-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","kernel-tools-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","kernel-tools-debuginfo-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","kernel-tools-devel-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","perf-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","perf-debuginfo-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","python3-perf-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm","python3-perf-debuginfo-6.6.0-145.0.3.134.oe2403sp3.aarch64.rpm"],"src":["kernel-6.6.0-145.0.3.134.oe2403sp3.src.rpm"],"x86_64":["bpftool-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","bpftool-debuginfo-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","kernel-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","kernel-debuginfo-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","kernel-debugsource-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","kernel-devel-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","kernel-extra-modules-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","kernel-headers-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","kernel-source-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","kernel-tools-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","kernel-tools-debuginfo-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","kernel-tools-devel-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","perf-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","perf-debuginfo-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","python3-perf-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm","python3-perf-debuginfo-6.6.0-145.0.3.134.oe2403sp3.x86_64.rpm"]}}],"references":[{"type":"ADVISORY","url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1949"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-68291"}],"database_specific":{"severity":"High"}}