« Volver al listado

CVE-2026-89985

Estado: RecibidaAlta (7.8)—

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

memcg: keep folio's objcg same as its node

memcg_reparent_objcgs() has an inherent assumption that a folio's objcg is the objcg of the folio's node. Folio migration across nodes breaks that assumption: the new folio simply inherits the old folio's objcg while living on a different node.

Once the assumption is broken, the reparenting of the folio's objcg and the reparenting of the folio's LRU list are no longer atomic. memcg_reparent_objcgs() handles one node per iteration and drops all the locks in between, so the objcg gets reparented in the iteration for the objcg's node while the LRU list gets spliced in the iteration for the folio's node.

Leer descripción completaMostrar menos

Any LRU operation on that folio in between resolves its lruvec through the objcg, and thus takes the lru_lock of the wrong memcg, not the lru_lock of the list the folio is actually on.

Fix this by selecting the objcg by folio_nid() at charge time, and by re-deriving it for the destination node in mem_cgroup_migrate() and mem_cgroup_replace_folio().

CVSS

Probabilidad de explotación (EPSS)

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.

Vulnerabilidad local en kernel Linux (AV:L, PR:L) explotable para escalada de privilegios. La corrupción de estructuras de datos de memoria en memcg puede causar DoS o corrupción de datos del 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 ProgramFilter Network TrafficExecution PreventionApplication Isolation and SandboxingExploit ProtectionUpdate Software

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Linux — Linux KernelAI

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-89985",
  "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": "f1cf8d2f36dc369688bbe61ce064fbd829dbc9e1",
              "lessThan": "6165478eaa3094eaee1d5e33b12520064faf043d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "f1cf8d2f36dc369688bbe61ce064fbd829dbc9e1",
              "lessThan": "bf4ade7dbd76d4ec8697840e4ebb15ed77c5ec26",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "mm/memcontrol.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "7.1"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "7.1",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "7.2.5",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "mm/memcontrol.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-09-16T11:17:09.547",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/6165478eaa3094eaee1d5e33b12520064faf043d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/bf4ade7dbd76d4ec8697840e4ebb15ed77c5ec26",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmemcg: keep folio's objcg same as its node\n\nmemcg_reparent_objcgs() has an inherent assumption that a folio's objcg is\nthe objcg of the folio's node.  Folio migration across nodes breaks that\nassumption: the new folio simply inherits the old folio's objcg while\nliving on a different node.\n\nOnce the assumption is broken, the reparenting of the folio's objcg and\nthe reparenting of the folio's LRU list are no longer atomic. \nmemcg_reparent_objcgs() handles one node per iteration and drops all the\nlocks in between, so the objcg gets reparented in the iteration for the\nobjcg's node while the LRU list gets spliced in the iteration for the\nfolio's node.  Any LRU operation on that folio in between resolves its\nlruvec through the objcg, and thus takes the lru_lock of the wrong memcg,\nnot the lru_lock of the list the folio is actually on.\n\nFix this by selecting the objcg by folio_nid() at charge time, and by\nre-deriving it for the destination node in mem_cgroup_migrate() and\nmem_cgroup_replace_folio()."
    }
  ],
  "lastModified": "2026-09-16T15:18:22.363",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}