{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f00a86d98a1ec3e99d352cda926fab767ba43b1f"
            },
            {
              "fixed": "65358d89dc9f1c25d9364b2b3ef0f3b47717f9ed"
            },
            {
              "fixed": "adc8b9c30d716c362646edb45662aa1c641a154a"
            },
            {
              "fixed": "8eff7cd4817e14dbe3b9952cce55ef52d1d38940"
            },
            {
              "fixed": "e99f2df433c63c86c93de1e5f08f16e404388756"
            },
            {
              "fixed": "1b495fa0d4927c88d88bf346bf311f2e26e860ed"
            },
            {
              "fixed": "9f32f38265014fac7f5dc9490fb01a638ce6e121"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.32"
            },
            {
              "fixed": "6.1.178"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.145"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.96"
            }
          ],
          "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-2026-64449.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nstaging: vme_user: bound slave read/write to the kern_buf size\n\nThe SLAVE-path helpers buffer_to_user() and buffer_from_user() copy\n'count' bytes into/out of the fixed-size kern_buf (size_buf ==\nPCI_BUF_SIZE == 0x20000, 128 KiB) using *ppos as the offset, without\nbounding *ppos + count against size_buf.\n\nvme_user_write()/vme_user_read() only clamp count to the VME window size\n(image_size = vme_get_size(resource)), which VME_SET_SLAVE sets from the\nuser-supplied slave.size -- validated against the VME address space (up\nto VME_A32_MAX = 4 GiB), not against PCI_BUF_SIZE.  When the window\nexceeds 128 KiB, a write()/read() copies past the kern_buf allocation.\n\nClamp count against size_buf in both helpers, with an early return when\n*ppos is already at/after the buffer end.  *ppos is \u003e= 0 here (the caller\nrejects negative offsets), so size_buf - *ppos cannot wrap.  This mirrors\nthe existing clamp in the MASTER-path helpers resource_to_user() /\nresource_from_user(), and matches the read()/write() convention of a\nshort transfer at end-of-buffer.\n\nFound by static analysis (CodeQL taint tracking + CBMC bounded model\nchecking) and confirmed dynamically under KASAN with the vme_fake bridge:\n\n  BUG: KASAN: slab-out-of-bounds in _copy_from_user+0x2d/0x80\n  Write of size 262144 at addr ffff888004100000 by task trigger/68\n    _copy_from_user+0x2d/0x80\n    vme_user_write+0x13e/0x240 [vme_user]\n    vfs_write+0x1b8/0x7a0\n    ksys_write+0xb8/0x150",
  "id": "CVE-2026-64449",
  "modified": "2026-09-05T03:30:50.733695444Z",
  "published": "2026-07-25T08:51:19.537Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1b495fa0d4927c88d88bf346bf311f2e26e860ed"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/65358d89dc9f1c25d9364b2b3ef0f3b47717f9ed"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8eff7cd4817e14dbe3b9952cce55ef52d1d38940"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9f32f38265014fac7f5dc9490fb01a638ce6e121"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/adc8b9c30d716c362646edb45662aa1c641a154a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e99f2df433c63c86c93de1e5f08f16e404388756"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64449.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64449"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "staging: vme_user: bound slave read/write to the kern_buf size"
}