{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "bea67dcc5eea0f6a213897a59b9e644977cd07e6"
            },
            {
              "fixed": "818416fef38759f23210de449663cd9d7e293d39"
            },
            {
              "fixed": "b415c00bf23df577a4a95673d00ae76687bcc1d4"
            },
            {
              "fixed": "6a4196d19f477524d2f92adca90fc1fbe9a0420a"
            },
            {
              "fixed": "63b02a9409cb5180398491b093e48bcb5315f5fb"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.12.0"
            },
            {
              "fixed": "6.12.97"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.39"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64416.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: swap_cgroup: fix NULL deref in lookup_swap_cgroup_id on swapless host\n\nlookup_swap_cgroup_id() passes swap_cgroup_ctrl[type].map to\n__swap_cgroup_id_lookup() without checking that the type was ever\nregistered via swap_cgroup_swapon().  On a swapless host every ctrl-\u003emap\nis NULL, so __swap_cgroup_id_lookup() dereferences NULL + a scaled\nswp_offset().\n\nSince commit bea67dcc5eea (\"mm: attempt to batch free swap entries for\nzap_pte_range()\"), zap_pte_range() -\u003e swap_pte_batch() calls\nlookup_swap_cgroup_id() on any non-present, non-none PTE that decodes as a\nreal swap entry, without first validating it against swap_info[].  A\nsingle PTE corrupted into a type-0 swap entry takes the host down at\nprocess exit.\n\nWe hit this in production on a swapless 6.12.58 host: ~1s of\n\"get_swap_device: Bad swap file entry 3f800204222bb\" (do_swap_page() being\ncorrectly defensive about the same entry) followed by\n\n  BUG: unable to handle page fault for address: 000003f800204220\n  RIP: 0010:lookup_swap_cgroup_id+0x2b/0x60\n  Call Trace:\n   swap_pte_batch+0xbf/0x230\n   zap_pte_range+0x4c8/0x780\n   unmap_page_range+0x190/0x3e0\n   exit_mmap+0xd9/0x3c0\n   do_exit+0x20c/0x4b0\n\nsyzbot has reported the identical stack.\n\nThe source of the PTE corruption is a separate bug; this change makes the\nteardown path as robust as the fault path already is.  Every other caller\nof lookup_swap_cgroup_id() is downstream of a get_swap_device() that has\nalready validated the entry, so the new branch is cold.",
  "id": "CVE-2026-64416",
  "modified": "2026-07-27T03:56:22.891719716Z",
  "published": "2026-07-25T08:50:55.997Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/63b02a9409cb5180398491b093e48bcb5315f5fb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6a4196d19f477524d2f92adca90fc1fbe9a0420a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/818416fef38759f23210de449663cd9d7e293d39"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b415c00bf23df577a4a95673d00ae76687bcc1d4"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64416.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64416"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "mm: swap_cgroup: fix NULL deref in lookup_swap_cgroup_id on swapless host"
}