{"api_version":"1","generated_at":"2026-05-13T07:40:33+00:00","cve":"CVE-2025-38491","urls":{"html":"https://cve.report/CVE-2025-38491","api":"https://cve.report/api/cve/CVE-2025-38491.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2025-38491","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-38491"},"summary":{"title":"mptcp: make fallback action and fallback decision atomic","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: make fallback action and fallback decision atomic\n\nSyzkaller reported the following splat:\n\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 __mptcp_do_fallback net/mptcp/protocol.h:1223 [inline]\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 mptcp_do_fallback net/mptcp/protocol.h:1244 [inline]\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 check_fully_established net/mptcp/options.c:982 [inline]\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 mptcp_incoming_options+0x21a8/0x2510 net/mptcp/options.c:1153\n  Modules linked in:\n  CPU: 1 UID: 0 PID: 7704 Comm: syz.3.1419 Not tainted 6.16.0-rc3-gbd5ce2324dba #20 PREEMPT(voluntary)\n  Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n  RIP: 0010:__mptcp_do_fallback net/mptcp/protocol.h:1223 [inline]\n  RIP: 0010:mptcp_do_fallback net/mptcp/protocol.h:1244 [inline]\n  RIP: 0010:check_fully_established net/mptcp/options.c:982 [inline]\n  RIP: 0010:mptcp_incoming_options+0x21a8/0x2510 net/mptcp/options.c:1153\n  Code: 24 18 e8 bb 2a 00 fd e9 1b df ff ff e8 b1 21 0f 00 e8 ec 5f c4 fc 44 0f b7 ac 24 b0 00 00 00 e9 54 f1 ff ff e8 d9 5f c4 fc 90 <0f> 0b 90 e9 b8 f4 ff ff e8 8b 2a 00 fd e9 8d e6 ff ff e8 81 2a 00\n  RSP: 0018:ffff8880a3f08448 EFLAGS: 00010246\n  RAX: 0000000000000000 RBX: ffff8880180a8000 RCX: ffffffff84afcf45\n  RDX: ffff888090223700 RSI: ffffffff84afdaa7 RDI: 0000000000000001\n  RBP: ffff888017955780 R08: 0000000000000001 R09: 0000000000000000\n  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000\n  R13: ffff8880180a8910 R14: ffff8880a3e9d058 R15: 0000000000000000\n  FS:  00005555791b8500(0000) GS:ffff88811c495000(0000) knlGS:0000000000000000\n  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n  CR2: 000000110c2800b7 CR3: 0000000058e44000 CR4: 0000000000350ef0\n  Call Trace:\n   <IRQ>\n   tcp_reset+0x26f/0x2b0 net/ipv4/tcp_input.c:4432\n   tcp_validate_incoming+0x1057/0x1b60 net/ipv4/tcp_input.c:5975\n   tcp_rcv_established+0x5b5/0x21f0 net/ipv4/tcp_input.c:6166\n   tcp_v4_do_rcv+0x5dc/0xa70 net/ipv4/tcp_ipv4.c:1925\n   tcp_v4_rcv+0x3473/0x44a0 net/ipv4/tcp_ipv4.c:2363\n   ip_protocol_deliver_rcu+0xba/0x480 net/ipv4/ip_input.c:205\n   ip_local_deliver_finish+0x2f1/0x500 net/ipv4/ip_input.c:233\n   NF_HOOK include/linux/netfilter.h:317 [inline]\n   NF_HOOK include/linux/netfilter.h:311 [inline]\n   ip_local_deliver+0x1be/0x560 net/ipv4/ip_input.c:254\n   dst_input include/net/dst.h:469 [inline]\n   ip_rcv_finish net/ipv4/ip_input.c:447 [inline]\n   NF_HOOK include/linux/netfilter.h:317 [inline]\n   NF_HOOK include/linux/netfilter.h:311 [inline]\n   ip_rcv+0x514/0x810 net/ipv4/ip_input.c:567\n   __netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:5975\n   __netif_receive_skb+0x1f/0x120 net/core/dev.c:6088\n   process_backlog+0x301/0x1360 net/core/dev.c:6440\n   __napi_poll.constprop.0+0xba/0x550 net/core/dev.c:7453\n   napi_poll net/core/dev.c:7517 [inline]\n   net_rx_action+0xb44/0x1010 net/core/dev.c:7644\n   handle_softirqs+0x1d0/0x770 kernel/softirq.c:579\n   do_softirq+0x3f/0x90 kernel/softirq.c:480\n   </IRQ>\n   <TASK>\n   __local_bh_enable_ip+0xed/0x110 kernel/softirq.c:407\n   local_bh_enable include/linux/bottom_half.h:33 [inline]\n   inet_csk_listen_stop+0x2c5/0x1070 net/ipv4/inet_connection_sock.c:1524\n   mptcp_check_listen_stop.part.0+0x1cc/0x220 net/mptcp/protocol.c:2985\n   mptcp_check_listen_stop net/mptcp/mib.h:118 [inline]\n   __mptcp_close+0x9b9/0xbd0 net/mptcp/protocol.c:3000\n   mptcp_close+0x2f/0x140 net/mptcp/protocol.c:3066\n   inet_release+0xed/0x200 net/ipv4/af_inet.c:435\n   inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:487\n   __sock_release+0xb3/0x270 net/socket.c:649\n   sock_close+0x1c/0x30 net/socket.c:1439\n   __fput+0x402/0xb70 fs/file_table.c:465\n   task_work_run+0x150/0x240 kernel/task_work.c:227\n   resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]\n   exit_to_user_mode_loop+0xd4\n---truncated---","state":"PUBLISHED","assigner":"Linux","published_at":"2025-07-28 12:15:31","updated_at":"2026-05-12 13:16:51"},"problem_types":["CWE-667"],"metrics":[{"version":"3.1","source":"nvd@nist.gov","type":"Primary","score":"5.5","severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}}],"references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html","name":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html","refsource":"af854a3a-2127-422b-91ae-364da2661108","tags":["Third Party Advisory"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/75a4c9ab8a7af0d76b31ccd1188ed178c38b35d2","name":"https://git.kernel.org/stable/c/75a4c9ab8a7af0d76b31ccd1188ed178c38b35d2","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f8a1d9b18c5efc76784f5a326e905f641f839894","name":"https://git.kernel.org/stable/c/f8a1d9b18c5efc76784f5a326e905f641f839894","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/54999dea879fecb761225e28f274b40662918c30","name":"https://git.kernel.org/stable/c/54999dea879fecb761225e28f274b40662918c30","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/1d82a8fe6ee4afdc92f4e8808c9dad2a6095bbc5","name":"https://git.kernel.org/stable/c/1d82a8fe6ee4afdc92f4e8808c9dad2a6095bbc5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-032379.html","name":"https://cert-portal.siemens.com/productcert/html/ssa-032379.html","refsource":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/5586518bec27666c747cd52aabb62d485686d0bf","name":"https://git.kernel.org/stable/c/5586518bec27666c747cd52aabb62d485686d0bf","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-38491","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-38491","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 0530020a7c8f2204e784f0dbdc882bbd961fdbde 5586518bec27666c747cd52aabb62d485686d0bf git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 0530020a7c8f2204e784f0dbdc882bbd961fdbde 75a4c9ab8a7af0d76b31ccd1188ed178c38b35d2 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 0530020a7c8f2204e784f0dbdc882bbd961fdbde 54999dea879fecb761225e28f274b40662918c30 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 0530020a7c8f2204e784f0dbdc882bbd961fdbde 1d82a8fe6ee4afdc92f4e8808c9dad2a6095bbc5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 0530020a7c8f2204e784f0dbdc882bbd961fdbde f8a1d9b18c5efc76784f5a326e905f641f839894 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 609937aa962a62e93acfc04dd370b665e6152dfb git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6654efe264b014d8ea9fc38f79efb568b1b79069 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.19","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.19 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.149 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.101 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.40 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.15.8 6.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.16 * original_commit_for_fix","platforms":[]},{"source":"ADP","vendor":"Siemens","product":"SIMATIC CN 4100","version":"affected V5.0 custom","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2025","cve_id":"38491","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"linux","cpe5":"linux_kernel","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"providerMetadata":{"dateUpdated":"2025-11-03T17:38:59.794Z","orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE"},"references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"}],"title":"CVE Program Container"},{"affected":[{"defaultStatus":"unknown","product":"SIMATIC CN 4100","vendor":"Siemens","versions":[{"lessThan":"V5.0","status":"affected","version":"0","versionType":"custom"}]}],"providerMetadata":{"dateUpdated":"2026-05-12T12:05:09.215Z","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","shortName":"siemens-SADP"},"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-032379.html"}],"x_adpType":"supplier"}],"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/mptcp/options.c","net/mptcp/protocol.c","net/mptcp/protocol.h","net/mptcp/subflow.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"5586518bec27666c747cd52aabb62d485686d0bf","status":"affected","version":"0530020a7c8f2204e784f0dbdc882bbd961fdbde","versionType":"git"},{"lessThan":"75a4c9ab8a7af0d76b31ccd1188ed178c38b35d2","status":"affected","version":"0530020a7c8f2204e784f0dbdc882bbd961fdbde","versionType":"git"},{"lessThan":"54999dea879fecb761225e28f274b40662918c30","status":"affected","version":"0530020a7c8f2204e784f0dbdc882bbd961fdbde","versionType":"git"},{"lessThan":"1d82a8fe6ee4afdc92f4e8808c9dad2a6095bbc5","status":"affected","version":"0530020a7c8f2204e784f0dbdc882bbd961fdbde","versionType":"git"},{"lessThan":"f8a1d9b18c5efc76784f5a326e905f641f839894","status":"affected","version":"0530020a7c8f2204e784f0dbdc882bbd961fdbde","versionType":"git"},{"status":"affected","version":"609937aa962a62e93acfc04dd370b665e6152dfb","versionType":"git"},{"status":"affected","version":"6654efe264b014d8ea9fc38f79efb568b1b79069","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/mptcp/options.c","net/mptcp/protocol.c","net/mptcp/protocol.h","net/mptcp/subflow.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.19"},{"lessThan":"5.19","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.149","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.101","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.40","versionType":"semver"},{"lessThanOrEqual":"6.15.*","status":"unaffected","version":"6.15.8","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"6.16","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.149","versionStartIncluding":"5.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.101","versionStartIncluding":"5.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.40","versionStartIncluding":"5.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.15.8","versionStartIncluding":"5.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.16","versionStartIncluding":"5.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10.228","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.169","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: make fallback action and fallback decision atomic\n\nSyzkaller reported the following splat:\n\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 __mptcp_do_fallback net/mptcp/protocol.h:1223 [inline]\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 mptcp_do_fallback net/mptcp/protocol.h:1244 [inline]\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 check_fully_established net/mptcp/options.c:982 [inline]\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 mptcp_incoming_options+0x21a8/0x2510 net/mptcp/options.c:1153\n  Modules linked in:\n  CPU: 1 UID: 0 PID: 7704 Comm: syz.3.1419 Not tainted 6.16.0-rc3-gbd5ce2324dba #20 PREEMPT(voluntary)\n  Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n  RIP: 0010:__mptcp_do_fallback net/mptcp/protocol.h:1223 [inline]\n  RIP: 0010:mptcp_do_fallback net/mptcp/protocol.h:1244 [inline]\n  RIP: 0010:check_fully_established net/mptcp/options.c:982 [inline]\n  RIP: 0010:mptcp_incoming_options+0x21a8/0x2510 net/mptcp/options.c:1153\n  Code: 24 18 e8 bb 2a 00 fd e9 1b df ff ff e8 b1 21 0f 00 e8 ec 5f c4 fc 44 0f b7 ac 24 b0 00 00 00 e9 54 f1 ff ff e8 d9 5f c4 fc 90 <0f> 0b 90 e9 b8 f4 ff ff e8 8b 2a 00 fd e9 8d e6 ff ff e8 81 2a 00\n  RSP: 0018:ffff8880a3f08448 EFLAGS: 00010246\n  RAX: 0000000000000000 RBX: ffff8880180a8000 RCX: ffffffff84afcf45\n  RDX: ffff888090223700 RSI: ffffffff84afdaa7 RDI: 0000000000000001\n  RBP: ffff888017955780 R08: 0000000000000001 R09: 0000000000000000\n  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000\n  R13: ffff8880180a8910 R14: ffff8880a3e9d058 R15: 0000000000000000\n  FS:  00005555791b8500(0000) GS:ffff88811c495000(0000) knlGS:0000000000000000\n  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n  CR2: 000000110c2800b7 CR3: 0000000058e44000 CR4: 0000000000350ef0\n  Call Trace:\n   <IRQ>\n   tcp_reset+0x26f/0x2b0 net/ipv4/tcp_input.c:4432\n   tcp_validate_incoming+0x1057/0x1b60 net/ipv4/tcp_input.c:5975\n   tcp_rcv_established+0x5b5/0x21f0 net/ipv4/tcp_input.c:6166\n   tcp_v4_do_rcv+0x5dc/0xa70 net/ipv4/tcp_ipv4.c:1925\n   tcp_v4_rcv+0x3473/0x44a0 net/ipv4/tcp_ipv4.c:2363\n   ip_protocol_deliver_rcu+0xba/0x480 net/ipv4/ip_input.c:205\n   ip_local_deliver_finish+0x2f1/0x500 net/ipv4/ip_input.c:233\n   NF_HOOK include/linux/netfilter.h:317 [inline]\n   NF_HOOK include/linux/netfilter.h:311 [inline]\n   ip_local_deliver+0x1be/0x560 net/ipv4/ip_input.c:254\n   dst_input include/net/dst.h:469 [inline]\n   ip_rcv_finish net/ipv4/ip_input.c:447 [inline]\n   NF_HOOK include/linux/netfilter.h:317 [inline]\n   NF_HOOK include/linux/netfilter.h:311 [inline]\n   ip_rcv+0x514/0x810 net/ipv4/ip_input.c:567\n   __netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:5975\n   __netif_receive_skb+0x1f/0x120 net/core/dev.c:6088\n   process_backlog+0x301/0x1360 net/core/dev.c:6440\n   __napi_poll.constprop.0+0xba/0x550 net/core/dev.c:7453\n   napi_poll net/core/dev.c:7517 [inline]\n   net_rx_action+0xb44/0x1010 net/core/dev.c:7644\n   handle_softirqs+0x1d0/0x770 kernel/softirq.c:579\n   do_softirq+0x3f/0x90 kernel/softirq.c:480\n   </IRQ>\n   <TASK>\n   __local_bh_enable_ip+0xed/0x110 kernel/softirq.c:407\n   local_bh_enable include/linux/bottom_half.h:33 [inline]\n   inet_csk_listen_stop+0x2c5/0x1070 net/ipv4/inet_connection_sock.c:1524\n   mptcp_check_listen_stop.part.0+0x1cc/0x220 net/mptcp/protocol.c:2985\n   mptcp_check_listen_stop net/mptcp/mib.h:118 [inline]\n   __mptcp_close+0x9b9/0xbd0 net/mptcp/protocol.c:3000\n   mptcp_close+0x2f/0x140 net/mptcp/protocol.c:3066\n   inet_release+0xed/0x200 net/ipv4/af_inet.c:435\n   inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:487\n   __sock_release+0xb3/0x270 net/socket.c:649\n   sock_close+0x1c/0x30 net/socket.c:1439\n   __fput+0x402/0xb70 fs/file_table.c:465\n   task_work_run+0x150/0x240 kernel/task_work.c:227\n   resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]\n   exit_to_user_mode_loop+0xd4\n---truncated---"}],"providerMetadata":{"dateUpdated":"2026-05-11T21:29:02.773Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/5586518bec27666c747cd52aabb62d485686d0bf"},{"url":"https://git.kernel.org/stable/c/75a4c9ab8a7af0d76b31ccd1188ed178c38b35d2"},{"url":"https://git.kernel.org/stable/c/54999dea879fecb761225e28f274b40662918c30"},{"url":"https://git.kernel.org/stable/c/1d82a8fe6ee4afdc92f4e8808c9dad2a6095bbc5"},{"url":"https://git.kernel.org/stable/c/f8a1d9b18c5efc76784f5a326e905f641f839894"}],"title":"mptcp: make fallback action and fallback decision atomic","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2025-38491","datePublished":"2025-07-28T11:21:59.852Z","dateReserved":"2025-04-16T04:51:24.021Z","dateUpdated":"2026-05-12T12:05:09.215Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2025-07-28 12:15:31","lastModifiedDate":"2026-05-12 13:16:51","problem_types":["CWE-667"],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":3.6}]},"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10.228","versionEndExcluding":"5.11","matchCriteriaId":"7CEF9F93-A67A-45C9-9C51-0024664ACC19"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.169","versionEndExcluding":"5.16","matchCriteriaId":"9C85693E-DA17-43CB-991E-0810328B64A7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.19","versionEndExcluding":"6.1.149","matchCriteriaId":"C1860945-7136-4B12-9B55-D522EF9C2FFD"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.6.101","matchCriteriaId":"686C7A1C-35F3-495D-9825-94B5BCED2705"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"6.12.40","matchCriteriaId":"0099D5A4-B157-4D36-8858-982C7D579030"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"6.15.8","matchCriteriaId":"C7AFE5B0-F3B1-4D30-B8BF-EDA0385C4746"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:*","matchCriteriaId":"6D4894DB-CCFE-4602-B1BF-3960B2E19A01"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.16:rc2:*:*:*:*:*:*","matchCriteriaId":"09709862-E348-4378-8632-5A7813EDDC86"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.16:rc3:*:*:*:*:*:*","matchCriteriaId":"415BF58A-8197-43F5-B3D7-D1D63057A26E"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.16:rc4:*:*:*:*:*:*","matchCriteriaId":"A0517869-312D-4429-80C2-561086E1421C"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.16:rc5:*:*:*:*:*:*","matchCriteriaId":"85421F4E-C863-4ABF-B4B4-E887CC2F7F92"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.16:rc6:*:*:*:*:*:*","matchCriteriaId":"3827F0D4-5FEE-4181-B267-5A45E7CA11FC"}]}]},{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*","matchCriteriaId":"FA6FEEC2-9F11-4643-8827-749718254FED"}]}]}]},"legacy_mitre":{"record":{"CveYear":"2025","CveId":"38491","Ordinal":"1","Title":"mptcp: make fallback action and fallback decision atomic","CVE":"CVE-2025-38491","Year":"2025"},"notes":[{"CveYear":"2025","CveId":"38491","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: make fallback action and fallback decision atomic\n\nSyzkaller reported the following splat:\n\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 __mptcp_do_fallback net/mptcp/protocol.h:1223 [inline]\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 mptcp_do_fallback net/mptcp/protocol.h:1244 [inline]\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 check_fully_established net/mptcp/options.c:982 [inline]\n  WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 mptcp_incoming_options+0x21a8/0x2510 net/mptcp/options.c:1153\n  Modules linked in:\n  CPU: 1 UID: 0 PID: 7704 Comm: syz.3.1419 Not tainted 6.16.0-rc3-gbd5ce2324dba #20 PREEMPT(voluntary)\n  Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n  RIP: 0010:__mptcp_do_fallback net/mptcp/protocol.h:1223 [inline]\n  RIP: 0010:mptcp_do_fallback net/mptcp/protocol.h:1244 [inline]\n  RIP: 0010:check_fully_established net/mptcp/options.c:982 [inline]\n  RIP: 0010:mptcp_incoming_options+0x21a8/0x2510 net/mptcp/options.c:1153\n  Code: 24 18 e8 bb 2a 00 fd e9 1b df ff ff e8 b1 21 0f 00 e8 ec 5f c4 fc 44 0f b7 ac 24 b0 00 00 00 e9 54 f1 ff ff e8 d9 5f c4 fc 90 <0f> 0b 90 e9 b8 f4 ff ff e8 8b 2a 00 fd e9 8d e6 ff ff e8 81 2a 00\n  RSP: 0018:ffff8880a3f08448 EFLAGS: 00010246\n  RAX: 0000000000000000 RBX: ffff8880180a8000 RCX: ffffffff84afcf45\n  RDX: ffff888090223700 RSI: ffffffff84afdaa7 RDI: 0000000000000001\n  RBP: ffff888017955780 R08: 0000000000000001 R09: 0000000000000000\n  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000\n  R13: ffff8880180a8910 R14: ffff8880a3e9d058 R15: 0000000000000000\n  FS:  00005555791b8500(0000) GS:ffff88811c495000(0000) knlGS:0000000000000000\n  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n  CR2: 000000110c2800b7 CR3: 0000000058e44000 CR4: 0000000000350ef0\n  Call Trace:\n   <IRQ>\n   tcp_reset+0x26f/0x2b0 net/ipv4/tcp_input.c:4432\n   tcp_validate_incoming+0x1057/0x1b60 net/ipv4/tcp_input.c:5975\n   tcp_rcv_established+0x5b5/0x21f0 net/ipv4/tcp_input.c:6166\n   tcp_v4_do_rcv+0x5dc/0xa70 net/ipv4/tcp_ipv4.c:1925\n   tcp_v4_rcv+0x3473/0x44a0 net/ipv4/tcp_ipv4.c:2363\n   ip_protocol_deliver_rcu+0xba/0x480 net/ipv4/ip_input.c:205\n   ip_local_deliver_finish+0x2f1/0x500 net/ipv4/ip_input.c:233\n   NF_HOOK include/linux/netfilter.h:317 [inline]\n   NF_HOOK include/linux/netfilter.h:311 [inline]\n   ip_local_deliver+0x1be/0x560 net/ipv4/ip_input.c:254\n   dst_input include/net/dst.h:469 [inline]\n   ip_rcv_finish net/ipv4/ip_input.c:447 [inline]\n   NF_HOOK include/linux/netfilter.h:317 [inline]\n   NF_HOOK include/linux/netfilter.h:311 [inline]\n   ip_rcv+0x514/0x810 net/ipv4/ip_input.c:567\n   __netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:5975\n   __netif_receive_skb+0x1f/0x120 net/core/dev.c:6088\n   process_backlog+0x301/0x1360 net/core/dev.c:6440\n   __napi_poll.constprop.0+0xba/0x550 net/core/dev.c:7453\n   napi_poll net/core/dev.c:7517 [inline]\n   net_rx_action+0xb44/0x1010 net/core/dev.c:7644\n   handle_softirqs+0x1d0/0x770 kernel/softirq.c:579\n   do_softirq+0x3f/0x90 kernel/softirq.c:480\n   </IRQ>\n   <TASK>\n   __local_bh_enable_ip+0xed/0x110 kernel/softirq.c:407\n   local_bh_enable include/linux/bottom_half.h:33 [inline]\n   inet_csk_listen_stop+0x2c5/0x1070 net/ipv4/inet_connection_sock.c:1524\n   mptcp_check_listen_stop.part.0+0x1cc/0x220 net/mptcp/protocol.c:2985\n   mptcp_check_listen_stop net/mptcp/mib.h:118 [inline]\n   __mptcp_close+0x9b9/0xbd0 net/mptcp/protocol.c:3000\n   mptcp_close+0x2f/0x140 net/mptcp/protocol.c:3066\n   inet_release+0xed/0x200 net/ipv4/af_inet.c:435\n   inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:487\n   __sock_release+0xb3/0x270 net/socket.c:649\n   sock_close+0x1c/0x30 net/socket.c:1439\n   __fput+0x402/0xb70 fs/file_table.c:465\n   task_work_run+0x150/0x240 kernel/task_work.c:227\n   resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]\n   exit_to_user_mode_loop+0xd4\n---truncated---","Type":"Description","Title":"mptcp: make fallback action and fallback decision atomic"}]}}}