{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "960b589f86c74ce582922fcb996103271081f4de"
            },
            {
              "fixed": "c502fa9f094cb03d1d1685c71e2105ab359bc2b8"
            },
            {
              "fixed": "a6ae4511c07b91f597e461406c6330f0d4ff810e"
            },
            {
              "fixed": "1406c4e0ed1eaf8a29801ab1163d00fb7ee4359a"
            },
            {
              "fixed": "0b9e4bbfb7c949151e3acd44ed4aa33614d2e110"
            },
            {
              "fixed": "81af4137a30c4c2dc694dea8cacb180bd66000ef"
            },
            {
              "fixed": "5424e678f9b304e148cf5dcc047cffc7a56a3bb5"
            },
            {
              "fixed": "9a2d9d4e657b23dc21f24cf139e3aeff0b61341f"
            },
            {
              "fixed": "df4601653201de21b487c3e7fffd464790cab808"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.14.0"
            },
            {
              "fixed": "5.10.259"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.210"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.176"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.140"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.86"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.27"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.0.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46086.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: use a stable FDB dst snapshot in RCU readers\n\nLocal FDB entries can be rewritten in place by `fdb_delete_local()`, which\nupdates `f-\u003edst` to another port or to `NULL` while keeping the entry\nalive. Several bridge RCU readers inspect `f-\u003edst`, including\n`br_fdb_fillbuf()` through the `brforward_read()` sysfs path.\n\nThese readers currently load `f-\u003edst` multiple times and can therefore\nobserve inconsistent values across the check and later dereference.\nIn `br_fdb_fillbuf()`, this means a concurrent local-FDB update can change\n`f-\u003edst` after the NULL check and before the `port_no` dereference,\nleading to a NULL-ptr-deref.\n\nFix this by taking a single `READ_ONCE()` snapshot of `f-\u003edst` in each\naffected RCU reader and using that snapshot for the rest of the access\nsequence. Also publish the in-place `f-\u003edst` updates in `fdb_delete_local()`\nwith `WRITE_ONCE()` so the readers and writer use matching access patterns.",
  "id": "CVE-2026-46086",
  "modified": "2026-07-15T01:49:05.394994846Z",
  "published": "2026-05-27T12:58:28.137Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0b9e4bbfb7c949151e3acd44ed4aa33614d2e110"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1406c4e0ed1eaf8a29801ab1163d00fb7ee4359a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5424e678f9b304e148cf5dcc047cffc7a56a3bb5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/81af4137a30c4c2dc694dea8cacb180bd66000ef"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9a2d9d4e657b23dc21f24cf139e3aeff0b61341f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a6ae4511c07b91f597e461406c6330f0d4ff810e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c502fa9f094cb03d1d1685c71e2105ab359bc2b8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/df4601653201de21b487c3e7fffd464790cab808"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46086.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46086"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "net: bridge: use a stable FDB dst snapshot in RCU readers"
}