CVE-2021-47427

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This results in a iscsi_task use after free, because the common\ncleanup code will do a put on the iscsi_task.\n\nThis reverts the goto and moves the iscsi_get_conn() to after we've checked\nif the iscsi_task is valid."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL"}, "scenarios": [{"lang": "en", "value": "AV:N - This is the iSCSI initiator path; a remote target peer can induce SCSI command timeouts and then send completions over TCP so the abort handler hits the buggy early-completion path, making the flaw reachable via the network protocol.\nAC:L - The attacker controlling the iSCSI target controls both sides of the race by withholding responses to force EH abort and then completing the task while abort runs, so success does not depend on conditions outside their influence.\nPR:N - A malicious or compromised iSCSI target needs no privileges on the victim host; once a logged-in session exists (typical SAN/cloud block deployment), the peer can trigger the UAF without local credentials.\nUI:N - No additional user action is required beyond an already-established iSCSI session with in-flight I/O, which is normal for persistent SAN and iSCSI-rooted systems.\nS:U - The UAF corrupts initiator kernel memory in the same host kernel authority and does not cross a VM, IOMMU, or other security boundary.\nC:H - Use-after-free of iscsi_task enables reclaim and controlled reuse of the freed object, which can be leveraged for arbitrary kernel memory disclosure.\nI:H - The same iscsi_task UAF enables heap spray and corruption of adjacent kernel objects, providing write/control-flow primitives suitable for integrity compromise and code execution.\nA:H - The extra put can free the task while still in use or take a NULL task path, causing kernel oops/panic and full availability loss."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/scsi/libiscsi.c"], "versions": [{"version": "d39df158518ccc3bf24ee18082b5e100c8f014aa", "lessThan": "1642f51ac0d4f2b55d5748094c49ff8f7191b93c", "status": "affected", "versionType": "git"}, {"version": "d39df158518ccc3bf24ee18082b5e100c8f014aa", "lessThan": "258aad75c62146453d03028a44f2f1590d58e1f6", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/scsi/libiscsi.c"], "versions": [{"version": "5.14", "status": "affected"}, {"version": "0", "lessThan": "5.14", "status": "unaffected", "versionType": "semver"}, {"version": "5.14.12", "lessThanOrEqual": "5.14.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "5.14.12"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "5.15"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/1642f51ac0d4f2b55d5748094c49ff8f7191b93c"}, {"url": "https://git.kernel.org/stable/c/258aad75c62146453d03028a44f2f1590d58e1f6"}], "title": "scsi: iscsi: Fix iscsi_task use after free", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T05:39:59.381Z"}, "title": "CVE Program Container", "references": [{"url": "https://git.kernel.org/stable/c/1642f51ac0d4f2b55d5748094c49ff8f7191b93c", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/258aad75c62146453d03028a44f2f1590d58e1f6", "tags": ["x_transferred"]}]}, {"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2021-47427", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2024-09-10T15:37:44.486165Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-09-11T17:33:37.669Z"}}]}}

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This results in a iscsi_task use after free, because the common\ncleanup code will do a put on the iscsi_task.\n\nThis reverts the goto and moves the iscsi_get_conn() to after we've checked\nif the iscsi_task is valid."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.14.12", "versionStartIncluding": "5.14"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15", "versionStartIncluding": "5.14"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:47:46.574Z"}}}, "cveMetadata": {"cveId": "CVE-2021-47427", "state": "PUBLISHED", "dateUpdated": "2026-08-05T08:47:46.574Z", "dateReserved": "2024-05-21T14:58:30.828Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2024-05-21T15:04:13.244Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

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This results in a iscsi_task use after free, because the common\ncleanup code will do a put on the iscsi_task.\n\nThis reverts the goto and moves the iscsi_get_conn() to after we've checked\nif the iscsi_task is valid."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: scsi: iscsi: corrige el uso after free de iscsi_task. Confirmaci\u00f3n d39df158518c (\"scsi: iscsi: Have abort handler get ref to conn\") se agregaron llamadas iscsi_get_conn()/iscsi_put_conn() durante el manejo de abortos pero luego tambi\u00e9n cambi\u00f3 el manejo del caso en el que detectamos una tarea ya completada y ahora terminamos haciendo un acceso al c\u00f3digo com\u00fan de put/cleanup. Esto da como resultado un uso de iscsi_task despu\u00e9s de la liberaci\u00f3n, porque el c\u00f3digo de limpieza com\u00fan colocar\u00e1 iscsi_task. Esto revierte el ir a y mueve iscsi_get_conn() a despu\u00e9s de haber verificado si iscsi_task es v\u00e1lido."}], "id": "CVE-2021-47427", "lastModified": "2026-08-04T10:17:02.990", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "nvd@nist.gov", "type": "Primary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2021-47427", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2024-09-10T15:37:44.486165Z", "version": "2.0.3"}}]}, "published": "2024-05-21T15:15:28.117", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/1642f51ac0d4f2b55d5748094c49ff8f7191b93c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/258aad75c62146453d03028a44f2f1590d58e1f6"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/1642f51ac0d4f2b55d5748094c49ff8f7191b93c"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/258aad75c62146453d03028a44f2f1590d58e1f6"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: scsi: iscsi: Fix iscsi_task use after free", "id": "2282305", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2282305"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.4", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-416", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nscsi: iscsi: Fix iscsi_task use after free\nCommit d39df158518c (\"scsi: iscsi: Have abort handler get ref to conn\")\nadded iscsi_get_conn()/iscsi_put_conn() calls during abort handling but\nthen also changed the handling of the case where we detect an already\ncompleted task where we now end up doing a goto to the common put/cleanup\ncode. This results in a iscsi_task use after free, because the common\ncleanup code will do a put on the iscsi_task.\nThis reverts the goto and moves the iscsi_get_conn() to after we've checked\nif the iscsi_task is valid."], "name": "CVE-2021-47427", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2024-05-21T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-47427\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47427\nhttps://lore.kernel.org/linux-cve-announce/2024052157-CVE-2021-47427-ffc6@gregkh/T"], "threat_severity": "Low"}

{}