{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/damon/sysfs-schemes: protect memcg_path kfree() with damon_sysfs_lock\n\nPatch series \"mm/damon/sysfs-schemes: fix use-after-free for [memcg_]path\".\n\nReads of \u0027memcg_path\u0027 and \u0027path\u0027 files in DAMON sysfs interface could race\nwith their writes, results in use-after-free.  Fix those.\n\n\nThis patch (of 2):\n\ndamon_sysfs_scheme_filter-\u003emmecg_path can be read and written by users,\nvia DAMON sysfs memcg_path file.  It can also be indirectly read, for the\nparameters {on,off}line committing to DAMON.  The reads for parameters\ncommitting are protected by damon_sysfs_lock to avoid the sysfs files\nbeing destroyed while any of the parameters are being read.  But the\nuser-driven direct reads and writes are not protected by any lock, while\nthe write is deallocating the memcg_path-pointing buffer.  As a result,\nthe readers could read the already freed buffer (user-after-free).  Note\nthat the user-reads don\u0027t race when the same open file is used by the\nwriter, due to kernfs\u0027s open file locking.  Nonetheless, doing the reads\nand writes with separate open files would be common.  Fix it by protecting\nboth the user-direct reads and writes with damon_sysfs_lock."
    }
  ],
  "id": "CVE-2026-46121",
  "lastModified": "2026-05-28T13:44:01.663",
  "metrics": {},
  "published": "2026-05-28T10:16:27.600",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/1e68eb96e8beb1abefd12dd22c5637795d8a877e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/b1e9f2d5870776347edef927f9bb3ea19b8e3abb"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/baecc45ad60e621ef14d6c1e7f41ef36bbfdf910"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c88802d0e8edd14b6cd2daf3000f99adbc4c85c5"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/eafd6f5372d29b0dd213799b92c2c9c7ad31d7da"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-46121"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-28T10:16:27Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/damon/sysfs-schemes: protect memcg_path kfree() with damon_sysfs_lock\n\nPatch series \"mm/damon/sysfs-schemes: fix use-after-free for [memcg_]path\".\n\nReads of \u0027memcg_path\u0027 and \u0027path\u0027 files in DAMON sysfs interface could race\nwith their writes, results in use-after-free.  Fix those.\n\n\nThis patch (of 2):\n\ndamon_sysfs_scheme_filter-\u003emmecg_path can be read and written by users,\nvia DAMON sysfs memcg_path file.  It can also be indirectly read, for the\nparameters {on,off}line committing to DAMON.  The reads for parameters\ncommitting are protected by damon_sysfs_lock to avoid the sysfs files\nbeing destroyed while any of the parameters are being read.  But the\nuser-driven direct reads and writes are not protected by any lock, while\nthe write is deallocating the memcg_path-pointing buffer.  As a result,\nthe readers could read the already freed buffer (user-after-free).  Note\nthat the user-reads don\u0027t race when the same open file is used by the\nwriter, due to kernfs\u0027s open file locking.  Nonetheless, doing the reads\nand writes with separate open files would be common.  Fix it by protecting\nboth the user-direct reads and writes with damon_sysfs_lock.",
  "id": "GHSA-496c-fq9m-2rhq",
  "modified": "2026-05-28T12:30:29Z",
  "published": "2026-05-28T12:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46121"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1e68eb96e8beb1abefd12dd22c5637795d8a877e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b1e9f2d5870776347edef927f9bb3ea19b8e3abb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/baecc45ad60e621ef14d6c1e7f41ef36bbfdf910"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c88802d0e8edd14b6cd2daf3000f99adbc4c85c5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/eafd6f5372d29b0dd213799b92c2c9c7ad31d7da"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

{
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    "category": "csaf_vex",
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        "url": "https://www.first.org/tlp/"
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    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2026-46121 mm/damon/sysfs-schemes: protect memcg_path kfree() with damon_sysfs_lock - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-46121.json"
      },
      {
        "category": "external",
        "summary": "Microsoft Support Lifecycle",
        "url": "https://support.microsoft.com/lifecycle"
      },
      {
        "category": "external",
        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "mm/damon/sysfs-schemes: protect memcg_path kfree() with damon_sysfs_lock",
    "tracking": {
      "current_release_date": "2026-05-29T01:09:12.000Z",
      "generator": {
        "date": "2026-05-29T07:23:45.840Z",
        "engine": {
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      "id": "msrc_CVE-2026-46121",
      "initial_release_date": "2026-05-02T00:00:00.000Z",
      "revision_history": [
        {
          "date": "2026-05-29T01:09:12.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
        }
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      "status": "final",
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              {
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                "name": "3.0",
                "product": {
                  "name": "Azure Linux 3.0",
                  "product_id": "17084"
                }
              }
            ],
            "category": "product_name",
            "name": "Azure Linux"
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
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  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-46121",
      "notes": [
        {
          "category": "general",
          "text": "Linux",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
        "under_investigation": [
          "17084-1"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-46121 mm/damon/sysfs-schemes: protect memcg_path kfree() with damon_sysfs_lock - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-46121.json"
        }
      ],
      "title": "mm/damon/sysfs-schemes: protect memcg_path kfree() with damon_sysfs_lock"
    }
  ]
}