{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.1.176-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.86-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.0.4-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  net: bridge: use a stable FDB dst snapshot in RCU readers  Local FDB entries can be rewritten in place by `fdb_delete_local()`, which updates `f-\u003edst` to another port or to `NULL` while keeping the entry alive. Several bridge RCU readers inspect `f-\u003edst`, including `br_fdb_fillbuf()` through the `brforward_read()` sysfs path.  These readers currently load `f-\u003edst` multiple times and can therefore observe inconsistent values across the check and later dereference. In `br_fdb_fillbuf()`, this means a concurrent local-FDB update can change `f-\u003edst` after the NULL check and before the `port_no` dereference, leading to a NULL-ptr-deref.  Fix this by taking a single `READ_ONCE()` snapshot of `f-\u003edst` in each affected RCU reader and using that snapshot for the rest of the access sequence. Also publish the in-place `f-\u003edst` updates in `fdb_delete_local()` with `WRITE_ONCE()` so the readers and writer use matching access patterns.",
  "id": "DEBIAN-CVE-2026-46086",
  "modified": "2026-09-09T08:47:24.449687468Z",
  "published": "2026-05-27T14:17:30.080Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-46086"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-46086"
  ]
}