CVE-2025-21719

Estado: ModificadaAlta (7.1)—

In the Linux kernel, the following vulnerability has been resolved:

ipmr: do not call mr_mfc_uses_dev() for unres entries

syzbot found that calling mr_mfc_uses_dev() for unres entries would crash [1], because c->mfc_un.res.minvif / c->mfc_un.res.maxvif alias to "struct sk_buff_head unresolved", which contain two pointers.

This code never worked, lets remove it.

Detalles técnicos trazas, registros y código del informe original

[1]
Unable to handle kernel paging request at virtual address ffff5fff2d536613
KASAN: maybe wild-memory-access in range [0xfffefff96a9b3098-0xfffefff96a9b309f]
Modules linked in:
CPU: 1 UID: 0 PID: 7321 Comm: syz.0.16 Not tainted 6.13.0-rc7-syzkaller-g1950a0af2d55 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : mr_mfc_uses_dev net/ipv4/ipmr_base.c:290 [inline]
 pc : mr_table_dump+0x5a4/0x8b0 net/ipv4/ipmr_base.c:334
 lr : mr_mfc_uses_dev net/ipv4/ipmr_base.c:289 [inline]
 lr : mr_table_dump+0x694/0x8b0 net/ipv4/ipmr_base.c:334
Call trace:
  mr_mfc_uses_dev net/ipv4/ipmr_base.c:290 [inline] (P)
  mr_table_dump+0x5a4/0x8b0 net/ipv4/ipmr_base.c:334 (P)
  mr_rtm_dumproute+0x254/0x454 net/ipv4/ipmr_base.c:382
  ipmr_rtm_dumproute+0x248/0x4b4 net/ipv4/ipmr.c:2648
  rtnl_dump_all+0x2e4/0x4e8 net/core/rtnetlink.c:4327
  rtnl_dumpit+0x98/0x1d0 net/core/rtnetlink.c:6791
  netlink_dump+0x4f0/0xbc0 net/netlink/af_netlink.c:2317
  netlink_recvmsg+0x56c/0xe64 net/netlink/af_netlink.c:1973
  sock_recvmsg_nosec net/socket.c:1033 [inline]
  sock_recvmsg net/socket.c:1055 [inline]
  sock_read_iter+0x2d8/0x40c net/socket.c:1125
  new_sync_read fs/read_write.c:484 [inline]
  vfs_read+0x740/0x970 fs/read_write.c:565
  ksys_read+0x15c/0x26c fs/read_write.c:708

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Puntuación base: 7.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.21%
Percentil entre todas las CVEs puntuadas: 10
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.

ExplotaciónT1068 Exploitation for Privilege Escalationprivilege escalation85 %
Impacto principalT1499.004 Application or System Exploitationimpact90 %

AV:L, PR:L, UI:N indica escalada local sin interacción. El crash en kernel (wild-memory-access) causa DoS de aplicación/sistema.

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

Threat Intelligence Program Filter Network Traffic Execution Prevention Application Isolation and Sandboxing Exploit Protection Update Software

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-125

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2025-21719",
  "cveTags": [],
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        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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          "integrityImpact": "NONE",
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          "attackComplexity": "LOW",
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              "lessThan": "*",
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  "published": "2025-02-27T02:15:15.580",
  "references": [
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      "url": "https://git.kernel.org/stable/c/15a901361ec3fb1c393f91880e1cbf24ec0a88bd",
      "tags": [
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    {
      "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
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    {
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-265688.html",
      "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
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  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipmr: do not call mr_mfc_uses_dev() for unres entries\n\nsyzbot found that calling mr_mfc_uses_dev() for unres entries\nwould crash [1], because c->mfc_un.res.minvif / c->mfc_un.res.maxvif\nalias to \"struct sk_buff_head unresolved\", which contain two pointers.\n\nThis code never worked, lets remove it.\n\n[1]\nUnable to handle kernel paging request at virtual address ffff5fff2d536613\nKASAN: maybe wild-memory-access in range [0xfffefff96a9b3098-0xfffefff96a9b309f]\nModules linked in:\nCPU: 1 UID: 0 PID: 7321 Comm: syz.0.16 Not tainted 6.13.0-rc7-syzkaller-g1950a0af2d55 #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024\npstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)\n pc : mr_mfc_uses_dev net/ipv4/ipmr_base.c:290 [inline]\n pc : mr_table_dump+0x5a4/0x8b0 net/ipv4/ipmr_base.c:334\n lr : mr_mfc_uses_dev net/ipv4/ipmr_base.c:289 [inline]\n lr : mr_table_dump+0x694/0x8b0 net/ipv4/ipmr_base.c:334\nCall trace:\n  mr_mfc_uses_dev net/ipv4/ipmr_base.c:290 [inline] (P)\n  mr_table_dump+0x5a4/0x8b0 net/ipv4/ipmr_base.c:334 (P)\n  mr_rtm_dumproute+0x254/0x454 net/ipv4/ipmr_base.c:382\n  ipmr_rtm_dumproute+0x248/0x4b4 net/ipv4/ipmr.c:2648\n  rtnl_dump_all+0x2e4/0x4e8 net/core/rtnetlink.c:4327\n  rtnl_dumpit+0x98/0x1d0 net/core/rtnetlink.c:6791\n  netlink_dump+0x4f0/0xbc0 net/netlink/af_netlink.c:2317\n  netlink_recvmsg+0x56c/0xe64 net/netlink/af_netlink.c:1973\n  sock_recvmsg_nosec net/socket.c:1033 [inline]\n  sock_recvmsg net/socket.c:1055 [inline]\n  sock_read_iter+0x2d8/0x40c net/socket.c:1125\n  new_sync_read fs/read_write.c:484 [inline]\n  vfs_read+0x740/0x970 fs/read_write.c:565\n  ksys_read+0x15c/0x26c fs/read_write.c:708"
    },
    {
      "lang": "es",
      "value": "En el núcleo de Linux, se ha resuelto la siguiente vulnerabilidad: ipmr: no llamar a mr_mfc_uses_dev() para entradas no resueltas syzbot descubrió que llamar a mr_mfc_uses_dev() para entradas no resueltas provocaría un bloqueo [1], porque c-&gt;mfc_un.res.minvif / c-&gt;mfc_un.res.maxvif son alias de \"struct sk_buff_head unresolved\", que contienen dos punteros. Este código nunca funcionó, eliminémoslo. [1] No se puede manejar la solicitud de paginación del kernel en la dirección virtual ffff5fff2d536613 KASAN: tal vez un acceso a memoria salvaje en el rango [0xfffefff96a9b3098-0xfffefff96a9b309f] Módulos vinculados: CPU: 1 UID: 0 PID: 7321 Comm: syz.0.16 No contaminado 6.13.0-rc7-syzkaller-g1950a0af2d55 #0 Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 13/09/2024 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : mr_mfc_uses_dev net/ipv4/ipmr_base.c:290 [en línea] pc : mr_table_dump+0x5a4/0x8b0 net/ipv4/ipmr_base.c:334 lr : mr_mfc_uses_dev net/ipv4/ipmr_base.c:289 [en línea] lr : mr_table_dump+0x694/0x8b0 net/ipv4/ipmr_base.c:334 Rastreo de llamadas: mr_mfc_uses_dev net/ipv4/ipmr_base.c:290 [en línea] (P) mr_table_dump+0x5a4/0x8b0 net/ipv4/ipmr_base.c:334 (P) mr_rtm_dumproute+0x254/0x454 net/ipv4/ipmr_base.c:382 ipmr_rtm_dumproute+0x248/0x4b4 net/ipv4/ipmr.c:2648 rtnl_dump_all+0x2e4/0x4e8 net/core/rtnetlink.c:4327 rtnl_dumpit+0x98/0x1d0 net/core/rtnetlink.c:6791 netlink_dump+0x4f0/0xbc0 net/netlink/af_netlink.c:2317 netlink_recvmsg+0x56c/0xe64 net/netlink/af_netlink.c:1973 sock_recvmsg_nosec net/socket.c:1033 [en línea] sock_recvmsg net/socket.c:1055 [en línea] sock_read_iter+0x2d8/0x40c net/socket.c:1125 new_sync_read fs/read_write.c:484 [en línea] vfs_read+0x740/0x970 fs/read_write.c:565 ksys_read+0x15c/0x26c fs/read_write.c:708"
    }
  ],
  "lastModified": "2026-07-30T06:20:39.593",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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}