{"api_version":"1","generated_at":"2026-07-23T12:07:23+00:00","cve":"CVE-2026-43364","urls":{"html":"https://cve.report/CVE-2026-43364","api":"https://cve.report/api/cve/CVE-2026-43364.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-43364","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-43364"},"summary":{"title":"ublk: fix NULL pointer dereference in ublk_ctrl_set_size()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nublk: fix NULL pointer dereference in ublk_ctrl_set_size()\n\nublk_ctrl_set_size() unconditionally dereferences ub->ub_disk via\nset_capacity_and_notify() without checking if it is NULL.\n\nub->ub_disk is NULL before UBLK_CMD_START_DEV completes (it is only\nassigned in ublk_ctrl_start_dev()) and after UBLK_CMD_STOP_DEV runs\n(ublk_detach_disk() sets it to NULL). Since the UBLK_CMD_UPDATE_SIZE\nhandler performs no state validation, a user can trigger a NULL pointer\ndereference by sending UPDATE_SIZE to a device that has been added but\nnot yet started, or one that has been stopped.\n\nFix this by checking ub->ub_disk under ub->mutex before dereferencing\nit, and returning -ENODEV if the disk is not available.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-08 15:16:47","updated_at":"2026-05-15 16:14:44"},"problem_types":["CWE-476"],"metrics":[{"version":"3.1","source":"nvd@nist.gov","type":"Primary","score":"5.5","severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}}],"references":[{"url":"https://git.kernel.org/stable/c/f13fe6794726755a43090cb680c4c58cea6aa5f1","name":"https://git.kernel.org/stable/c/f13fe6794726755a43090cb680c4c58cea6aa5f1","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/25966fc097691e5c925ad080f64a2f19c5fd940a","name":"https://git.kernel.org/stable/c/25966fc097691e5c925ad080f64a2f19c5fd940a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/c28d945bfa92e15147e93b73f95345b9bec979b0","name":"https://git.kernel.org/stable/c/c28d945bfa92e15147e93b73f95345b9bec979b0","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-43364","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43364","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 98b995660bff011d8e00af03abd74ac7d1ac1390 f13fe6794726755a43090cb680c4c58cea6aa5f1 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 98b995660bff011d8e00af03abd74ac7d1ac1390 c28d945bfa92e15147e93b73f95345b9bec979b0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 98b995660bff011d8e00af03abd74ac7d1ac1390 25966fc097691e5c925ad080f64a2f19c5fd940a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.16","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.16 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.20 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.9 6.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2026","cve_id":"43364","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"linux","cpe5":"linux_kernel","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"43364","cve":"CVE-2026-43364","epss":"0.000170000","percentile":"0.041320000","score_date":"2026-05-12","updated_at":"2026-05-13 00:11:53"},"legacy_qids":[]},"source_records":{"cve_program":{"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":"f13fe6794726755a43090cb680c4c58cea6aa5f1","status":"affected","version":"98b995660bff011d8e00af03abd74ac7d1ac1390","versionType":"git"},{"lessThan":"c28d945bfa92e15147e93b73f95345b9bec979b0","status":"affected","version":"98b995660bff011d8e00af03abd74ac7d1ac1390","versionType":"git"},{"lessThan":"25966fc097691e5c925ad080f64a2f19c5fd940a","status":"affected","version":"98b995660bff011d8e00af03abd74ac7d1ac1390","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":"6.16"},{"lessThan":"6.16","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.20","versionType":"semver"},{"lessThanOrEqual":"6.19.*","status":"unaffected","version":"6.19.9","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.0","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.20","versionStartIncluding":"6.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.19.9","versionStartIncluding":"6.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0","versionStartIncluding":"6.16","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nublk: fix NULL pointer dereference in ublk_ctrl_set_size()\n\nublk_ctrl_set_size() unconditionally dereferences ub->ub_disk via\nset_capacity_and_notify() without checking if it is NULL.\n\nub->ub_disk is NULL before UBLK_CMD_START_DEV completes (it is only\nassigned in ublk_ctrl_start_dev()) and after UBLK_CMD_STOP_DEV runs\n(ublk_detach_disk() sets it to NULL). Since the UBLK_CMD_UPDATE_SIZE\nhandler performs no state validation, a user can trigger a NULL pointer\ndereference by sending UPDATE_SIZE to a device that has been added but\nnot yet started, or one that has been stopped.\n\nFix this by checking ub->ub_disk under ub->mutex before dereferencing\nit, and returning -ENODEV if the disk is not available."}],"providerMetadata":{"dateUpdated":"2026-05-11T22:23:09.555Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/f13fe6794726755a43090cb680c4c58cea6aa5f1"},{"url":"https://git.kernel.org/stable/c/c28d945bfa92e15147e93b73f95345b9bec979b0"},{"url":"https://git.kernel.org/stable/c/25966fc097691e5c925ad080f64a2f19c5fd940a"}],"title":"ublk: fix NULL pointer dereference in ublk_ctrl_set_size()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-43364","datePublished":"2026-05-08T14:21:17.654Z","dateReserved":"2026-05-01T14:12:56.005Z","dateUpdated":"2026-05-11T22:23:09.555Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-08 15:16:47","lastModifiedDate":"2026-05-15 16:14:44","problem_types":["CWE-476"],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":3.6}]},"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"6.18.20","matchCriteriaId":"1C570CE1-BC61-4BE6-9393-FD0CA8637367"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19","versionEndExcluding":"6.19.9","matchCriteriaId":"E825E7C3-FEAC-4FD3-8A81-78D7387948C9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*","matchCriteriaId":"F253B622-8837-4245-BCE5-A7BF8FC76A16"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*","matchCriteriaId":"4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*","matchCriteriaId":"F666C8D8-6538-46D4-B318-87610DE64C34"}]}]}]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"43364","Ordinal":"1","Title":"ublk: fix NULL pointer dereference in ublk_ctrl_set_size()","CVE":"CVE-2026-43364","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"43364","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nublk: fix NULL pointer dereference in ublk_ctrl_set_size()\n\nublk_ctrl_set_size() unconditionally dereferences ub->ub_disk via\nset_capacity_and_notify() without checking if it is NULL.\n\nub->ub_disk is NULL before UBLK_CMD_START_DEV completes (it is only\nassigned in ublk_ctrl_start_dev()) and after UBLK_CMD_STOP_DEV runs\n(ublk_detach_disk() sets it to NULL). Since the UBLK_CMD_UPDATE_SIZE\nhandler performs no state validation, a user can trigger a NULL pointer\ndereference by sending UPDATE_SIZE to a device that has been added but\nnot yet started, or one that has been stopped.\n\nFix this by checking ub->ub_disk under ub->mutex before dereferencing\nit, and returning -ENODEV if the disk is not available.","Type":"Description","Title":"ublk: fix NULL pointer dereference in ublk_ctrl_set_size()"}]}}}