{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f889491380582b4ba2981cf0b0d7d6a40fb30ab7"
            },
            {
              "fixed": "5224bd37e37d36076a550d99b2aebba33939fd95"
            },
            {
              "fixed": "54617e9119be2eb728ecdd8d977b99c99d4c498a"
            },
            {
              "fixed": "13fa6f32a56a386a82bd7451644c494beed034af"
            },
            {
              "fixed": "cf363a7a02ce132ef1f58084fdb13e1a3b7da7e7"
            },
            {
              "fixed": "6fa3e9b1fe856259555a7e22f3f3082e7827fd9b"
            },
            {
              "fixed": "f1e21108e3ddfcce62f6cad4ebd7b5674543c9e6"
            },
            {
              "fixed": "b70ebe0bba254e093dd5fd4c0c170941ce83eb85"
            },
            {
              "fixed": "de845981da67a6b049080c87e605130b0c30adc5"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.11.0"
            },
            {
              "fixed": "5.10.265"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.216"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.183"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.152"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.104"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.45"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74580.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nvhost: reset the vring metadata cache on vring reconfiguration\n\nvq-\u003emeta_iotlb[] caches the vhost_iotlb_map that backs each vring\nmetadata region, and iotlb_access_ok() returns early on a cache hit,\ntaking the hit as proof that the region has already been validated:\n\n\tif (vhost_vq_meta_fetch(vq, addr, len, type))\n\t\treturn true;\n\nThe cache is reset on VHOST_IOTLB_UPDATE and VHOST_IOTLB_INVALIDATE, on\ndevice IOTLB (re)initialisation and on vq reset, but not when\nVHOST_SET_VRING_ADDR replaces vq-\u003edesc, vq-\u003eavail and vq-\u003eused, nor when\nVHOST_SET_VRING_NUM changes the region sizes.\n\nWith a device IOTLB attached both ioctls are accepted while the vq is\nlive, and neither validates the addresses at ioctl time: vq_access_ok()\nand vq_log_used_access_ok() return true early because the addresses are\nGIOVAs, deferring validation to prefetch time.  Once the cache has been\npopulated that deferred validation no longer runs -- vq_meta_prefetch()\nhits the stale entry and returns true -- and vhost_vq_meta_fetch() keeps\ntranslating through the old mapping as\n\n\tmap-\u003eaddr + addr - map-\u003estart\n\nfor an address the mapping no longer covers.  vhost_copy_to_user() and\nvhost_copy_from_user() consume the result with __copy_to_user() and\n__copy_from_user(), which do not check it either, so a subsequent used\nring update or descriptor fetch accesses memory outside the region the\nIOTLB actually maps.\n\nReset the metadata cache whenever the vring is reconfigured, so the new\naddresses are pushed back through iotlb_access_ok()'s slow path.",
  "id": "CVE-2026-74580",
  "modified": "2026-08-27T11:31:10.045159675Z",
  "published": "2026-08-21T16:31:54.076Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/13fa6f32a56a386a82bd7451644c494beed034af"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5224bd37e37d36076a550d99b2aebba33939fd95"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/54617e9119be2eb728ecdd8d977b99c99d4c498a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6fa3e9b1fe856259555a7e22f3f3082e7827fd9b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b70ebe0bba254e093dd5fd4c0c170941ce83eb85"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cf363a7a02ce132ef1f58084fdb13e1a3b7da7e7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/de845981da67a6b049080c87e605130b0c30adc5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f1e21108e3ddfcce62f6cad4ebd7b5674543c9e6"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74580.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74580"
    },
    {
      "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:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "vhost: reset the vring metadata cache on vring reconfiguration"
}