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CVE-2026-46042

Estado: AnalizadaMedia (5.5)—

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

mm/mempolicy: fix memory leaks in weighted_interleave_auto_store()

weighted_interleave_auto_store() fetches old_wi_state inside the if (!input) block only. This causes two memory leaks:

Fix both leaks by moving the old_wi_state fetch before the input check, making it unconditional. This also allows a unified early return for both "true" and "false" when the requested mode matches the current mode.

Reviewed by: Donet Tom <donettom@linux.ibm.com>

Detalles técnicos trazas, registros y código del informe original
1. When a user writes "false" and the current mode is already manual,
   the function returns early without freeing the freshly allocated
   new_wi_state.

2. When a user writes "true", old_wi_state stays NULL because the
   fetch is skipped entirely. The old state is then overwritten by
   rcu_assign_pointer() but never freed, since the cleanup path is
   gated on old_wi_state being non-NULL. A user can trigger this
   repeatedly by writing "1" in a loop.

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).

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

Referencias

JSON original (NVD)

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          "attackVector": "LOCAL",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
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  "published": "2026-05-27T14:17:23.633",
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  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/mempolicy: fix memory leaks in weighted_interleave_auto_store()\n\nweighted_interleave_auto_store() fetches old_wi_state inside the if\n(!input) block only.  This causes two memory leaks:\n\n1. When a user writes \"false\" and the current mode is already manual,\n   the function returns early without freeing the freshly allocated\n   new_wi_state.\n\n2. When a user writes \"true\", old_wi_state stays NULL because the\n   fetch is skipped entirely. The old state is then overwritten by\n   rcu_assign_pointer() but never freed, since the cleanup path is\n   gated on old_wi_state being non-NULL. A user can trigger this\n   repeatedly by writing \"1\" in a loop.\n\nFix both leaks by moving the old_wi_state fetch before the input check,\nmaking it unconditional.  This also allows a unified early return for both\n\"true\" and \"false\" when the requested mode matches the current mode.\n\nReviewed by: Donet Tom <donettom@linux.ibm.com>"
    }
  ],
  "lastModified": "2026-06-17T10:52:57.130",
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}