CVE-2026-74472 (GCVE-0-2026-74472)

Vulnerability from cvelistv5 – Published: 2026-08-15 12:27 – Updated: 2026-08-19 16:37
VLAI
Title
ublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev()
Summary
In the Linux kernel, the following vulnerability has been resolved: ublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev() ublk_ctrl_add_dev() memcpy()s the userspace ublksrv_ctrl_dev_info into ub->dev_info and then fixes up the fields the driver owns, but misses ->state and ->ublksrv_pid. A device added with ->state = UBLK_S_DEV_LIVE passes the "->state != UBLK_S_DEV_DEAD" test that ublk_stop_dev_unlocked() uses as its proxy for "a disk is attached", while ->ub_disk is still NULL, so DEL_DEV right after ADD_DEV oopses in del_gendisk(). UBLK_S_DEV_QUIESCED plus UBLK_F_USER_RECOVERY dies one step earlier, in ublk_force_abort_dev(). A poisoned ->state also gets START_USER_RECOVERY and the char device read/write path onto a device that was never started, and wedges START_DEV at -EEXIST. A poisoned ->ublksrv_pid just makes GET_DEV_INFO report an unrelated task as the ublk server. Reset both after the memcpy(), as ublk_detach_disk() does. Userspace only ever reads these back, so correcting them silently breaks nothing. ADD_DEV has copied ->state in unsanitized since ublk was merged, but back then it was harmless: the gendisk was allocated during ADD_DEV, and both teardown and the START_DEV -EEXIST check keyed off disk_live() rather than ->state. The oops became reachable once the disk allocation moved to START_DEV and those checks switched to ->state.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 6d9e6dfdf3b207701471f364121c67eefb000682 , < 787c944502e7e63d20a9201bada77e0dd924f458 (git)
Affected: 6d9e6dfdf3b207701471f364121c67eefb000682 , < ee41b00858ca65b4428e99efe39a4277c1f043d2 (git)
Affected: 6d9e6dfdf3b207701471f364121c67eefb000682 , < b67ce16b26ad0f14cfd6071013840aa95f823bea (git)
Affected: 6d9e6dfdf3b207701471f364121c67eefb000682 , < 205feb72e5beb3140e4e1403b6cff30cf739bab9 (git)
Affected: 6d9e6dfdf3b207701471f364121c67eefb000682 , < 127033b79383a3e78361d7e971588aa8849f5124 (git)
Affected: 6d9e6dfdf3b207701471f364121c67eefb000682 , < e65848e4ce352bac9e3465099354c8b8f845391f (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.0
Unaffected: 0 , < 6.0 (semver)
Unaffected: 6.1.183 , ≤ 6.1.* (semver)
Unaffected: 6.6.151 , ≤ 6.6.* (semver)
Unaffected: 6.12.103 , ≤ 6.12.* (semver)
Unaffected: 6.18.44 , ≤ 6.18.* (semver)
Unaffected: 7.1.8 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/block/ublk_drv.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "787c944502e7e63d20a9201bada77e0dd924f458",
              "status": "affected",
              "version": "6d9e6dfdf3b207701471f364121c67eefb000682",
              "versionType": "git"
            },
            {
              "lessThan": "ee41b00858ca65b4428e99efe39a4277c1f043d2",
              "status": "affected",
              "version": "6d9e6dfdf3b207701471f364121c67eefb000682",
              "versionType": "git"
            },
            {
              "lessThan": "b67ce16b26ad0f14cfd6071013840aa95f823bea",
              "status": "affected",
              "version": "6d9e6dfdf3b207701471f364121c67eefb000682",
              "versionType": "git"
            },
            {
              "lessThan": "205feb72e5beb3140e4e1403b6cff30cf739bab9",
              "status": "affected",
              "version": "6d9e6dfdf3b207701471f364121c67eefb000682",
              "versionType": "git"
            },
            {
              "lessThan": "127033b79383a3e78361d7e971588aa8849f5124",
              "status": "affected",
              "version": "6d9e6dfdf3b207701471f364121c67eefb000682",
              "versionType": "git"
            },
            {
              "lessThan": "e65848e4ce352bac9e3465099354c8b8f845391f",
              "status": "affected",
              "version": "6d9e6dfdf3b207701471f364121c67eefb000682",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/block/ublk_drv.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.0"
            },
            {
              "lessThan": "6.0",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.183",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.151",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.103",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.44",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.183",
                  "versionStartIncluding": "6.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.151",
                  "versionStartIncluding": "6.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.103",
                  "versionStartIncluding": "6.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.44",
                  "versionStartIncluding": "6.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.8",
                  "versionStartIncluding": "6.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev()\n\nublk_ctrl_add_dev() memcpy()s the userspace ublksrv_ctrl_dev_info into\nub-\u003edev_info and then fixes up the fields the driver owns, but misses\n-\u003estate and -\u003eublksrv_pid.\n\nA device added with -\u003estate = UBLK_S_DEV_LIVE passes the\n\"-\u003estate != UBLK_S_DEV_DEAD\" test that ublk_stop_dev_unlocked() uses as its\nproxy for \"a disk is attached\", while -\u003eub_disk is still NULL, so DEL_DEV\nright after ADD_DEV oopses in del_gendisk().  UBLK_S_DEV_QUIESCED plus\nUBLK_F_USER_RECOVERY dies one step earlier, in ublk_force_abort_dev().  A\npoisoned -\u003estate also gets START_USER_RECOVERY and the char device\nread/write path onto a device that was never started, and wedges START_DEV\nat -EEXIST.  A poisoned -\u003eublksrv_pid just makes GET_DEV_INFO report an\nunrelated task as the ublk server.\n\nReset both after the memcpy(), as ublk_detach_disk() does.  Userspace only\never reads these back, so correcting them silently breaks nothing.\n\nADD_DEV has copied -\u003estate in unsanitized since ublk was merged, but back\nthen it was harmless: the gendisk was allocated during ADD_DEV, and both\nteardown and the START_DEV -EEXIST check keyed off disk_live() rather than\n-\u003estate.  The oops became reachable once the disk allocation moved to\nSTART_DEV and those checks switched to -\u003estate."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-19T16:37:23.182Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/787c944502e7e63d20a9201bada77e0dd924f458"
        },
        {
          "url": "https://git.kernel.org/stable/c/ee41b00858ca65b4428e99efe39a4277c1f043d2"
        },
        {
          "url": "https://git.kernel.org/stable/c/b67ce16b26ad0f14cfd6071013840aa95f823bea"
        },
        {
          "url": "https://git.kernel.org/stable/c/205feb72e5beb3140e4e1403b6cff30cf739bab9"
        },
        {
          "url": "https://git.kernel.org/stable/c/127033b79383a3e78361d7e971588aa8849f5124"
        },
        {
          "url": "https://git.kernel.org/stable/c/e65848e4ce352bac9e3465099354c8b8f845391f"
        }
      ],
      "title": "ublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74472",
    "datePublished": "2026-08-15T12:27:08.759Z",
    "dateReserved": "2026-08-15T05:44:03.902Z",
    "dateUpdated": "2026-08-19T16:37:23.182Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-74472",
      "date": "2026-08-28",
      "epss": "0.00173",
      "percentile": "0.06785"
    },
    "microsoft_vex": {
      "current_release_date": "2026-08-23T14:59:11.000Z",
      "cve": "CVE-2026-74472",
      "id": "msrc_CVE-2026-74472",
      "initial_release_date": "2026-08-23T14:59:11.000Z",
      "product_status:known_not_affected": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "ublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev()",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-74472.json",
      "version": "1"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-74472\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-08-15T13:17:51.953\",\"lastModified\":\"2026-08-19T17:21:04.490\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev()\\n\\nublk_ctrl_add_dev() memcpy()s the userspace ublksrv_ctrl_dev_info into\\nub-\u003edev_info and then fixes up the fields the driver owns, but misses\\n-\u003estate and -\u003eublksrv_pid.\\n\\nA device added with -\u003estate = UBLK_S_DEV_LIVE passes the\\n\\\"-\u003estate != UBLK_S_DEV_DEAD\\\" test that ublk_stop_dev_unlocked() uses as its\\nproxy for \\\"a disk is attached\\\", while -\u003eub_disk is still NULL, so DEL_DEV\\nright after ADD_DEV oopses in del_gendisk().  UBLK_S_DEV_QUIESCED plus\\nUBLK_F_USER_RECOVERY dies one step earlier, in ublk_force_abort_dev().  A\\npoisoned -\u003estate also gets START_USER_RECOVERY and the char device\\nread/write path onto a device that was never started, and wedges START_DEV\\nat -EEXIST.  A poisoned -\u003eublksrv_pid just makes GET_DEV_INFO report an\\nunrelated task as the ublk server.\\n\\nReset both after the memcpy(), as ublk_detach_disk() does.  Userspace only\\never reads these back, so correcting them silently breaks nothing.\\n\\nADD_DEV has copied -\u003estate in unsanitized since ublk was merged, but back\\nthen it was harmless: the gendisk was allocated during ADD_DEV, and both\\nteardown and the START_DEV -EEXIST check keyed off disk_live() rather than\\n-\u003estate.  The oops became reachable once the disk allocation moved to\\nSTART_DEV and those checks switched to -\u003estate.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"drivers/block/ublk_drv.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6d9e6dfdf3b207701471f364121c67eefb000682\",\"lessThan\":\"787c944502e7e63d20a9201bada77e0dd924f458\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6d9e6dfdf3b207701471f364121c67eefb000682\",\"lessThan\":\"ee41b00858ca65b4428e99efe39a4277c1f043d2\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6d9e6dfdf3b207701471f364121c67eefb000682\",\"lessThan\":\"b67ce16b26ad0f14cfd6071013840aa95f823bea\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6d9e6dfdf3b207701471f364121c67eefb000682\",\"lessThan\":\"205feb72e5beb3140e4e1403b6cff30cf739bab9\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6d9e6dfdf3b207701471f364121c67eefb000682\",\"lessThan\":\"127033b79383a3e78361d7e971588aa8849f5124\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6d9e6dfdf3b207701471f364121c67eefb000682\",\"lessThan\":\"e65848e4ce352bac9e3465099354c8b8f845391f\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"drivers/block/ublk_drv.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6.0\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"6.0\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.183\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.151\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.103\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.44\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.8\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/127033b79383a3e78361d7e971588aa8849f5124\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/205feb72e5beb3140e4e1403b6cff30cf739bab9\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/787c944502e7e63d20a9201bada77e0dd924f458\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/b67ce16b26ad0f14cfd6071013840aa95f823bea\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/e65848e4ce352bac9e3465099354c8b8f845391f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/ee41b00858ca65b4428e99efe39a4277c1f043d2\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-19T17:41:05+00:00",
      "cve": "CVE-2026-74472",
      "id": "CVE-2026-74472",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "76",
      "product_status:known_not_affected": "198",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: ublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74472.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.