CVE-2025-40258
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix race condition in mptcp_schedule_work() syzbot reported use-after-free in mptcp_schedule_work() [1] Issue here is that mptcp_schedule_work() schedules a work, then gets a refcount on sk->sk_refcnt if the work was scheduled. This refcount will be released by mptcp_worker(). [A] if (schedule_work(...)) { [B] sock_hold(sk); return true; } Problem is that mptcp_worker() can run immediately and complete before [B] We need instead : sock_hold(sk); if (schedule_work(...)) return true; sock_put(sk); [1] refcount_t: addition on 0; use-after-free. WARNING: CPU: 1 PID: 29 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25 Call Trace: <TASK> __refcount_add include/linux/refcount.h:-1 [inline] __refcount_inc include/linux/refcount.h:366 [inline] refcount_inc include/linux/refcount.h:383 [inline] sock_hold include/net/sock.h:816 [inline] mptcp_schedule_work+0x164/0x1a0 net/mptcp/protocol.c:943 mptcp_tout_timer+0x21/0xa0 net/mptcp/protocol.c:2316 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x648/0x970 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x22f/0x710 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] run_ktimerd+0xcf/0x190 kernel/softirq.c:1138 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Severity
CRITICAL
CVSS score
9.8
(v3.1)
Vulnerability status
Deferred
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-12-04 16:16:19.640000
Last modified
2026-10-19 21:10:00.160000
View original CVE JSON
{
"id": "CVE-2025-40258",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-12-04T16:16:19.640",
"lastModified": "2026-10-19T21:10:00.160",
"vulnStatus": "Deferred",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix race condition in mptcp_schedule_work()\n\nsyzbot reported use-after-free in mptcp_schedule_work() [1]\n\nIssue here is that mptcp_schedule_work() schedules a work,\nthen gets a refcount on sk->sk_refcnt if the work was scheduled.\nThis refcount will be released by mptcp_worker().\n\n[A] if (schedule_work(...)) {\n[B] sock_hold(sk);\n return true;\n }\n\nProblem is that mptcp_worker() can run immediately and complete before [B]\n\nWe need instead :\n\n sock_hold(sk);\n if (schedule_work(...))\n return true;\n sock_put(sk);\n\n[1]\nrefcount_t: addition on 0; use-after-free.\n WARNING: CPU: 1 PID: 29 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25\nCall Trace:\n <TASK>\n __refcount_add include/linux/refcount.h:-1 [inline]\n __refcount_inc include/linux/refcount.h:366 [inline]\n refcount_inc include/linux/refcount.h:383 [inline]\n sock_hold include/net/sock.h:816 [inline]\n mptcp_schedule_work+0x164/0x1a0 net/mptcp/protocol.c:943\n mptcp_tout_timer+0x21/0xa0 net/mptcp/protocol.c:2316\n call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747\n expire_timers kernel/time/timer.c:1798 [inline]\n __run_timers kernel/time/timer.c:2372 [inline]\n __run_timer_base+0x648/0x970 kernel/time/timer.c:2384\n run_timer_base kernel/time/timer.c:2393 [inline]\n run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403\n handle_softirqs+0x22f/0x710 kernel/softirq.c:622\n __do_softirq kernel/softirq.c:656 [inline]\n run_ktimerd+0xcf/0x190 kernel/softirq.c:1138\n smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160\n kthread+0x711/0x8a0 kernel/kthread.c:463\n ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158\n ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245"
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nmptcp: soluciona condición de carrera en mptcp_schedule_work()\n\nsyzbot informó uso después de liberación en mptcp_schedule_work() [1]\n\nEl problema aquí es que mptcp_schedule_work() programa una tarea,\nluego obtiene un contador de referencias en sk->sk_refcnt si la tarea fue programada.\nEste contador de referencias será liberado por mptcp_worker().\n\n[A] if (schedule_work(...)) {\n[B] sock_hold(sk);\n return true;\n }\n\nEl problema es que mptcp_worker() puede ejecutarse inmediatamente y completarse antes de [B]\n\nEn su lugar, necesitamos:\n\n sock_hold(sk);\n if (schedule_work(...))\n return true;\n sock_put(sk);\n\n[1]\nrefcount_t: adición en 0; uso después de liberación.\n WARNING: CPU: 1 PID: 29 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25\nTraza de Llamada:\n <TASK>\n __refcount_add include/linux/refcount.h:-1 [inline]\n __refcount_inc include/linux/refcount.h:366 [inline]\n refcount_inc include/linux/refcount.h:383 [inline]\n sock_hold include/net/sock.h:816 [inline]\n mptcp_schedule_work+0x164/0x1a0 net/mptcp/protocol.c:943\n mptcp_tout_timer+0x21/0xa0 net/mptcp/protocol.c:2316\n call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747\n expire_timers kernel/time/timer.c:1798 [inline]\n __run_timers kernel/time/timer.c:2372 [inline]\n __run_timer_base+0x648/0x970 kernel/time/timer.c:2384\n run_timer_base kernel/time/timer.c:2393 [inline]\n run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403\n handle_softirqs+0x22f/0x710 kernel/softirq.c:622\n __do_softirq kernel/softirq.c:656 [inline]\n run_ktimerd+0xcf/0x190 kernel/softirq.c:1138\n smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160\n kthread+0x711/0x8a0 kernel/kthread.c:463\n ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158\n ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245"
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"net/mptcp/protocol.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "3b1d6210a9577369103330b0d802b0bf74b65e7f",
"lessThan": "f865e6595acf33083168db76921e66ace8bf0e5b",
"versionType": "git",
"status": "affected"
},
{
"version": "3b1d6210a9577369103330b0d802b0bf74b65e7f",
"lessThan": "99908e2d601236842d705d5fd04fb349577316f5",
"versionType": "git",
"status": "affected"
},
{
"version": "3b1d6210a9577369103330b0d802b0bf74b65e7f",
"lessThan": "db4f7968a75250ca6c4ed70d0a78beabb2dcee18",
"versionType": "git",
"status": "affected"
},
{
"version": "3b1d6210a9577369103330b0d802b0bf74b65e7f",
"lessThan": "8f9ba1a99a89feef9b5867c15a0141a97e893309",
"versionType": "git",
"status": "affected"
},
{
"version": "3b1d6210a9577369103330b0d802b0bf74b65e7f",
"lessThan": "ac28dfddedf6f209190950fc71bcff65ec4ab47b",
"versionType": "git",
"status": "affected"
},
{
"version": "3b1d6210a9577369103330b0d802b0bf74b65e7f",
"lessThan": "3fc7723ed01d1130d4bf7063c50e0af60ecccbb4",
"versionType": "git",
"status": "affected"
},
{
"version": "3b1d6210a9577369103330b0d802b0bf74b65e7f",
"lessThan": "035bca3f017ee9dea3a5a756e77a6f7138cc6eea",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"net/mptcp/protocol.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "5.7",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.7",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.10.247",
"lessThanOrEqual": "5.10.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.197",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.159",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.118",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.60",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.17.10",
"lessThanOrEqual": "6.17.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
},
{
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"affectedData": [
{
"vendor": "Siemens",
"product": "RUGGEDCOM RST2428P",
"defaultStatus": "unknown",
"versions": [
{
"version": "0",
"lessThan": "V4.0",
"versionType": "custom",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"baseScore": 9.8,
"baseSeverity": "CRITICAL",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 3.9,
"impactScore": 5.9
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-06-16T19:42:15.474459Z",
"id": "CVE-2025-40258",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"references": [
{
"url": "https://git.kernel.org/stable/c/035bca3f017ee9dea3a5a756e77a6f7138cc6eea",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/3fc7723ed01d1130d4bf7063c50e0af60ecccbb4",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/8f9ba1a99a89feef9b5867c15a0141a97e893309",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/99908e2d601236842d705d5fd04fb349577316f5",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ac28dfddedf6f209190950fc71bcff65ec4ab47b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/db4f7968a75250ca6c4ed70d0a78beabb2dcee18",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f865e6595acf33083168db76921e66ace8bf0e5b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-253495.html",
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
}
]
}