{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-23321", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-01-13T15:37:45.996Z", "datePublished": "2026-03-25T10:27:15.125Z", "dateUpdated": "2026-07-14T12:46:34.892Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-23T16:04:34.546Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: pm: in-kernel: always mark signal+subflow endp as used\n\nSyzkaller managed to find a combination of actions that was generating\nthis warning:\n\n msk->pm.local_addr_used == 0\n WARNING: net/mptcp/pm_kernel.c:1071 at __mark_subflow_endp_available net/mptcp/pm_kernel.c:1071 [inline], CPU#1: syz.2.17/961\n WARNING: net/mptcp/pm_kernel.c:1071 at mptcp_nl_remove_subflow_and_signal_addr net/mptcp/pm_kernel.c:1103 [inline], CPU#1: syz.2.17/961\n WARNING: net/mptcp/pm_kernel.c:1071 at mptcp_pm_nl_del_addr_doit+0x81d/0x8f0 net/mptcp/pm_kernel.c:1210, CPU#1: syz.2.17/961\n Modules linked in:\n CPU: 1 UID: 0 PID: 961 Comm: syz.2.17 Not tainted 6.19.0-08368-gfafda3b4b06b #22 PREEMPT(full)\n Hardware name: QEMU Ubuntu 25.10 PC v2 (i440FX + PIIX, + 10.1 machine, 1996), BIOS 1.17.0-debian-1.17.0-1build1 04/01/2014\n RIP: 0010:__mark_subflow_endp_available net/mptcp/pm_kernel.c:1071 [inline]\n RIP: 0010:mptcp_nl_remove_subflow_and_signal_addr net/mptcp/pm_kernel.c:1103 [inline]\n RIP: 0010:mptcp_pm_nl_del_addr_doit+0x81d/0x8f0 net/mptcp/pm_kernel.c:1210\n Code: 89 c5 e8 46 30 6f fe e9 21 fd ff ff 49 83 ed 80 e8 38 30 6f fe 4c 89 ef be 03 00 00 00 e8 db 49 df fe eb ac e8 24 30 6f fe 90 <0f> 0b 90 e9 1d ff ff ff e8 16 30 6f fe eb 05 e8 0f 30 6f fe e8 9a\n RSP: 0018:ffffc90001663880 EFLAGS: 00010293\n RAX: ffffffff82de1a6c RBX: 0000000000000000 RCX: ffff88800722b500\n RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000\n RBP: ffff8880158b22d0 R08: 0000000000010425 R09: ffffffffffffffff\n R10: ffffffff82de18ba R11: 0000000000000000 R12: ffff88800641a640\n R13: ffff8880158b1880 R14: ffff88801ec3c900 R15: ffff88800641a650\n FS: 00005555722c3500(0000) GS:ffff8880f909d000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f66346e0f60 CR3: 000000001607c000 CR4: 0000000000350ef0\n Call Trace:\n \n genl_family_rcv_msg_doit+0x117/0x180 net/netlink/genetlink.c:1115\n genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]\n genl_rcv_msg+0x3a8/0x3f0 net/netlink/genetlink.c:1210\n netlink_rcv_skb+0x16d/0x240 net/netlink/af_netlink.c:2550\n genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219\n netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]\n netlink_unicast+0x3e9/0x4c0 net/netlink/af_netlink.c:1344\n netlink_sendmsg+0x4aa/0x5b0 net/netlink/af_netlink.c:1894\n sock_sendmsg_nosec net/socket.c:727 [inline]\n __sock_sendmsg+0xc9/0xf0 net/socket.c:742\n ____sys_sendmsg+0x272/0x3b0 net/socket.c:2592\n ___sys_sendmsg+0x2de/0x320 net/socket.c:2646\n __sys_sendmsg net/socket.c:2678 [inline]\n __do_sys_sendmsg net/socket.c:2683 [inline]\n __se_sys_sendmsg net/socket.c:2681 [inline]\n __x64_sys_sendmsg+0x110/0x1a0 net/socket.c:2681\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x143/0x440 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n RIP: 0033:0x7f66346f826d\n Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 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 e8 ff ff ff f7 d8 64 89 01 48\n RSP: 002b:00007ffc83d8bdc8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e\n RAX: ffffffffffffffda RBX: 00007f6634985fa0 RCX: 00007f66346f826d\n RDX: 00000000040000b0 RSI: 0000200000000740 RDI: 0000000000000007\n RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000\n R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6634985fa8\n R13: 00007f6634985fac R14: 0000000000000000 R15: 0000000000001770\n \n\nThe actions that caused that seem to be:\n\n - Set the MPTCP subflows limit to 0\n - Create an MPTCP endpoint with both the 'signal' and 'subflow' flags\n - Create a new MPTCP connection from a different address: an ADD_ADDR\n linked to the MPTCP endpoint will be sent ('signal' flag), but no\n subflows is initiated ('subflow' flag)\n - Remove the MPTCP endpoint\n\n---truncated---" } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/mptcp/pm_kernel.c" ], "versions": [ { "version": "d93cf38fad9f66397093432b8917971a92ee0146", "lessThan": "c5c877e140e5f46023a74a51e577ce5edd0a4be7", "status": "affected", "versionType": "git" }, { "version": "64815ba15880ce5f99df075fa4104fef170ac7e5", "lessThan": "05799c2f1ca5eb13d65764dda688d02021b65e06", "status": "affected", "versionType": "git" }, { "version": "85df533a787bf07bf4367ce2a02b822ff1fba1a3", "lessThan": "67f34ab318807989b57dfdb0f79e2d4e57018290", "status": "affected", "versionType": "git" }, { "version": "85df533a787bf07bf4367ce2a02b822ff1fba1a3", "lessThan": "a64aa7db39392add5be09dffaedbf1f0ce5554df", "status": "affected", "versionType": "git" }, { "version": "85df533a787bf07bf4367ce2a02b822ff1fba1a3", "lessThan": "198824ccfa64ffebd918bf99c939bd8170a4a4d8", "status": "affected", "versionType": "git" }, { "version": "85df533a787bf07bf4367ce2a02b822ff1fba1a3", "lessThan": "579a752464a64cb5f9139102f0e6b90a1f595ceb", "status": "affected", "versionType": "git" }, { "version": "0f21cc29bc13e86512621727a4388c8a7ad2716b", "status": "affected", "versionType": "git" }, { "version": "6.1.106", "lessThan": "6.1.167", "status": "affected", "versionType": "semver" }, { "version": "6.6.46", "lessThan": "6.6.130", "status": "affected", "versionType": "semver" }, { "version": "6.10.5", "lessThan": "6.11", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/mptcp/pm_kernel.c" ], "versions": [ { "version": "6.11", "status": "affected" }, { "version": "0", "lessThan": "6.11", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.167", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.130", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.78", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.17", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.7", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.106", "versionEndExcluding": "6.1.167" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.46", "versionEndExcluding": "6.6.130" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.12.78" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.18.17" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.19.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "7.0" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10.5" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/c5c877e140e5f46023a74a51e577ce5edd0a4be7" }, { "url": "https://git.kernel.org/stable/c/05799c2f1ca5eb13d65764dda688d02021b65e06" }, { "url": "https://git.kernel.org/stable/c/67f34ab318807989b57dfdb0f79e2d4e57018290" }, { "url": "https://git.kernel.org/stable/c/a64aa7db39392add5be09dffaedbf1f0ce5554df" }, { "url": "https://git.kernel.org/stable/c/198824ccfa64ffebd918bf99c939bd8170a4a4d8" }, { "url": "https://git.kernel.org/stable/c/579a752464a64cb5f9139102f0e6b90a1f595ceb" } ], "title": "mptcp: pm: in-kernel: always mark signal+subflow endp as used", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "x_adpType": "supplier", "providerMetadata": { "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "shortName": "siemens-SADP", "dateUpdated": "2026-07-14T12:46:34.892Z" }, "affected": [ { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" } ], "references": [ { "url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html" }, { "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html" } ] } ] } }