CVE-2025-40027
Estado: AplazadaAlta (7.8)—
In the Linux kernel, the following vulnerability has been resolved:
net/9p: fix double req put in p9_fd_cancelled
Syzkaller reports a KASAN issue as below:
This happens because of a race condition between:
Commit 74d6a5d56629 ("9p/trans_fd: Fix concurrency del of req_list in p9_fd_cancelled/p9_read_work") fixes a concurrency issue in the 9p filesystem client where the req_list could be deleted simultaneously by both p9_read_work and p9_fd_cancelled functions, but for the case where req->status equals REQ_STATUS_RCVD.
Update the check for req->status in p9_fd_cancelled to skip processing not just received requests, but anything that is not SENT, as whatever changed the state from SENT also removed the request from its list.
Leer descripción completaMostrar menos
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
[updated the check from status == RECV || status == ERROR to status != SENT]
Detalles técnicos trazas, registros y código del informe original
general protection fault, probably for non-canonical address 0xfbd59c0000000021: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdead000000000108-0xdead00000000010f]
CPU: 0 PID: 5083 Comm: syz-executor.2 Not tainted 6.1.134-syzkaller-00037-g855bd1d7d838 #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:__list_del include/linux/list.h:114 [inline]
RIP: 0010:__list_del_entry include/linux/list.h:137 [inline]
RIP: 0010:list_del include/linux/list.h:148 [inline]
RIP: 0010:p9_fd_cancelled+0xe9/0x200 net/9p/trans_fd.c:734
Call Trace:
<TASK>
p9_client_flush+0x351/0x440 net/9p/client.c:614
p9_client_rpc+0xb6b/0xc70 net/9p/client.c:734
p9_client_version net/9p/client.c:920 [inline]
p9_client_create+0xb51/0x1240 net/9p/client.c:1027
v9fs_session_init+0x1f0/0x18f0 fs/9p/v9fs.c:408
v9fs_mount+0xba/0xcb0 fs/9p/vfs_super.c:126
legacy_get_tree+0x108/0x220 fs/fs_context.c:632
vfs_get_tree+0x8e/0x300 fs/super.c:1573
do_new_mount fs/namespace.c:3056 [inline]
path_mount+0x6a6/0x1e90 fs/namespace.c:3386
do_mount fs/namespace.c:3399 [inline]
__do_sys_mount fs/namespace.c:3607 [inline]
__se_sys_mount fs/namespace.c:3584 [inline]
__x64_sys_mount+0x283/0x300 fs/namespace.c:3584
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x35/0x80 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
- The 9p client sending an invalid flush request and later cleaning it up;
- The 9p client in p9_read_work() canceled all pending requests.
Thread 1 Thread 2
...
p9_client_create()
...
p9_fd_create()
...
p9_conn_create()
...
// start Thread 2
INIT_WORK(&m->rq, p9_read_work);
p9_read_work()
...
p9_client_rpc()
...
...
p9_conn_cancel()
...
spin_lock(&m->req_lock);
...
p9_fd_cancelled()
...
...
spin_unlock(&m->req_lock);
// status rewrite
p9_client_cb(m->client, req, REQ_STATUS_ERROR)
// first remove
list_del(&req->req_list);
...
spin_lock(&m->req_lock)
...
// second remove
list_del(&req->req_list);
spin_unlock(&m->req_lock)
...CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.16%
- Percentil entre todas las CVEs puntuadas: 5
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1068Exploitation for Privilege Escalationprivilege escalation75 % - Impacto principal
T1499.004Application or System Exploitationimpact70 %
Vulnerabilidad de race condition en kernel Linux con PR:L (acceso local con privilegios) permite DoS por corrupción de memoria; sin ejecución remota de código confirmada.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
Referencias
- https://git.kernel.org/stable/c/0e0097005abc02c9f262370674f855625f4f3fb4
- https://git.kernel.org/stable/c/284e67a93b8c48952b6fc82129a8d3eb9dc73b06
- https://git.kernel.org/stable/c/448db01a48e1cdbbc31c995716a5dac1e52ba036
- https://git.kernel.org/stable/c/5c64c0b7b3446f7ed088a13bc8d7487d66534cbb
- https://git.kernel.org/stable/c/674b56aa57f9379854cb6798c3bbcef7e7b51ab7
- https://git.kernel.org/stable/c/716dceb19a9f8ff6c9d3aee5a771a93d6a47a0b6
- https://git.kernel.org/stable/c/94797b84cb9985022eb9cb3275c9497fbc883bb6
- https://git.kernel.org/stable/c/a5901a0dfb5964525990106706ae8b98db098226
- https://git.kernel.org/stable/c/c1db864270eb7fea94a9ef201da0c9dc1cbab7b8
JSON original (NVD)
Mostrar
{
"id": "CVE-2025-40027",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.8,
"attackVector": "LOCAL",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 1.8
}
]
},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "afd8d65411551839b7ab14a539d00075b2793451",
"lessThan": "a5901a0dfb5964525990106706ae8b98db098226",
"versionType": "git"
},
{
"status": "affected",
"version": "afd8d65411551839b7ab14a539d00075b2793451",
"lessThan": "5c64c0b7b3446f7ed088a13bc8d7487d66534cbb",
"versionType": "git"
},
{
"status": "affected",
"version": "afd8d65411551839b7ab14a539d00075b2793451",
"lessThan": "c1db864270eb7fea94a9ef201da0c9dc1cbab7b8",
"versionType": "git"
},
{
"status": "affected",
"version": "afd8d65411551839b7ab14a539d00075b2793451",
"lessThan": "0e0097005abc02c9f262370674f855625f4f3fb4",
"versionType": "git"
},
{
"status": "affected",
"version": "afd8d65411551839b7ab14a539d00075b2793451",
"lessThan": "284e67a93b8c48952b6fc82129a8d3eb9dc73b06",
"versionType": "git"
},
{
"status": "affected",
"version": "afd8d65411551839b7ab14a539d00075b2793451",
"lessThan": "716dceb19a9f8ff6c9d3aee5a771a93d6a47a0b6",
"versionType": "git"
},
{
"status": "affected",
"version": "afd8d65411551839b7ab14a539d00075b2793451",
"lessThan": "448db01a48e1cdbbc31c995716a5dac1e52ba036",
"versionType": "git"
},
{
"status": "affected",
"version": "afd8d65411551839b7ab14a539d00075b2793451",
"lessThan": "94797b84cb9985022eb9cb3275c9497fbc883bb6",
"versionType": "git"
},
{
"status": "affected",
"version": "afd8d65411551839b7ab14a539d00075b2793451",
"lessThan": "674b56aa57f9379854cb6798c3bbcef7e7b51ab7",
"versionType": "git"
}
],
"programFiles": [
"net/9p/trans_fd.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.15"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.15",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.4.301",
"versionType": "semver",
"lessThanOrEqual": "5.4.*"
},
{
"status": "unaffected",
"version": "5.10.246",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.195",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.156",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.111",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.52",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.16.12",
"versionType": "semver",
"lessThanOrEqual": "6.16.*"
},
{
"status": "unaffected",
"version": "6.17.2",
"versionType": "semver",
"lessThanOrEqual": "6.17.*"
},
{
"status": "unaffected",
"version": "6.18",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/9p/trans_fd.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2025-10-28T10:15:42.313",
"references": [
{
"url": "https://git.kernel.org/stable/c/0e0097005abc02c9f262370674f855625f4f3fb4",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/284e67a93b8c48952b6fc82129a8d3eb9dc73b06",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/448db01a48e1cdbbc31c995716a5dac1e52ba036",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/5c64c0b7b3446f7ed088a13bc8d7487d66534cbb",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/674b56aa57f9379854cb6798c3bbcef7e7b51ab7",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/716dceb19a9f8ff6c9d3aee5a771a93d6a47a0b6",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/94797b84cb9985022eb9cb3275c9497fbc883bb6",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/a5901a0dfb5964525990106706ae8b98db098226",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/c1db864270eb7fea94a9ef201da0c9dc1cbab7b8",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Deferred",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/9p: fix double req put in p9_fd_cancelled\n\nSyzkaller reports a KASAN issue as below:\n\ngeneral protection fault, probably for non-canonical address 0xfbd59c0000000021: 0000 [#1] PREEMPT SMP KASAN NOPTI\nKASAN: maybe wild-memory-access in range [0xdead000000000108-0xdead00000000010f]\nCPU: 0 PID: 5083 Comm: syz-executor.2 Not tainted 6.1.134-syzkaller-00037-g855bd1d7d838 #0\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014\nRIP: 0010:__list_del include/linux/list.h:114 [inline]\nRIP: 0010:__list_del_entry include/linux/list.h:137 [inline]\nRIP: 0010:list_del include/linux/list.h:148 [inline]\nRIP: 0010:p9_fd_cancelled+0xe9/0x200 net/9p/trans_fd.c:734\n\nCall Trace:\n <TASK>\n p9_client_flush+0x351/0x440 net/9p/client.c:614\n p9_client_rpc+0xb6b/0xc70 net/9p/client.c:734\n p9_client_version net/9p/client.c:920 [inline]\n p9_client_create+0xb51/0x1240 net/9p/client.c:1027\n v9fs_session_init+0x1f0/0x18f0 fs/9p/v9fs.c:408\n v9fs_mount+0xba/0xcb0 fs/9p/vfs_super.c:126\n legacy_get_tree+0x108/0x220 fs/fs_context.c:632\n vfs_get_tree+0x8e/0x300 fs/super.c:1573\n do_new_mount fs/namespace.c:3056 [inline]\n path_mount+0x6a6/0x1e90 fs/namespace.c:3386\n do_mount fs/namespace.c:3399 [inline]\n __do_sys_mount fs/namespace.c:3607 [inline]\n __se_sys_mount fs/namespace.c:3584 [inline]\n __x64_sys_mount+0x283/0x300 fs/namespace.c:3584\n do_syscall_x64 arch/x86/entry/common.c:51 [inline]\n do_syscall_64+0x35/0x80 arch/x86/entry/common.c:81\n entry_SYSCALL_64_after_hwframe+0x6e/0xd8\n\nThis happens because of a race condition between:\n\n- The 9p client sending an invalid flush request and later cleaning it up;\n- The 9p client in p9_read_work() canceled all pending requests.\n\n Thread 1 Thread 2\n ...\n p9_client_create()\n ...\n p9_fd_create()\n ...\n p9_conn_create()\n ...\n // start Thread 2\n INIT_WORK(&m->rq, p9_read_work);\n p9_read_work()\n ...\n p9_client_rpc()\n ...\n ...\n p9_conn_cancel()\n ...\n spin_lock(&m->req_lock);\n ...\n p9_fd_cancelled()\n ...\n ...\n spin_unlock(&m->req_lock);\n // status rewrite\n p9_client_cb(m->client, req, REQ_STATUS_ERROR)\n // first remove\n list_del(&req->req_list);\n ...\n\n spin_lock(&m->req_lock)\n ...\n // second remove\n list_del(&req->req_list);\n spin_unlock(&m->req_lock)\n ...\n\nCommit 74d6a5d56629 (\"9p/trans_fd: Fix concurrency del of req_list in\np9_fd_cancelled/p9_read_work\") fixes a concurrency issue in the 9p filesystem\nclient where the req_list could be deleted simultaneously by both\np9_read_work and p9_fd_cancelled functions, but for the case where req->status\nequals REQ_STATUS_RCVD.\n\nUpdate the check for req->status in p9_fd_cancelled to skip processing not\njust received requests, but anything that is not SENT, as whatever\nchanged the state from SENT also removed the request from its list.\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller.\n\n[updated the check from status == RECV || status == ERROR to status != SENT]"
}
],
"lastModified": "2026-07-30T06:24:06.753",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}