CVE-2021-47506

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If we\nthen exit nfs4_set_delegation without hashing the delegation, it will be\nfreed as soon as the callback is done with it, without ever being\nremoved from del_recall_lru.\n\nSymptoms show up later as use-after-free or list corruption warnings,\nusually in the laundromat thread.\n\nI suspect aba2072f4523 \"nfsd: grant read delegations to clients holding\nwrites\" made this bug easier to hit, but I looked as far back as v3.0\nand it looks to me it already had the same problem. So I'm not sure\nwhere the bug was introduced; it may have been there from the beginning."}], "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 - The vulnerable path is in the in-kernel NFS server (nfs4_set_delegation / nfsd4_cb_recall_prepare in fs/nfsd/nfs4state.c), reached when a remote NFSv4 client issues OPEN compounds over TCP/UDP 2049 that attempt to grant a read delegation.\nAC:L - A remote attacker controls both sides of the race by opening/requesting a delegation on one NFS client/session while concurrently issuing a conflicting open (e.g. write) from another client or session slot on separate nfsd threads, so success does not depend on conditions outside attacker influence.\nPR:N - Typical nfsd deployments use AUTH_SYS/AUTH_NULL with IP-based exports and no cryptographic authentication, so any host allowed by the export can EXCHANGE_ID/CREATE_SESSION/OPEN and exercise the delegation-grant path by self-asserting credentials.\nUI:N - The attacker alone drives the OPEN/delegation grant and the conflicting open that breaks the lease; no victim user or administrator action on the server is required.\nS:U - The use-after-free corrupts kernel slab memory (nfs4_delegation on del_recall_lru) within the host nfsd security authority and does not cross a VM, IOMMU, or other separate boundary.\nC:H - The unhashed delegation is freed while still linked on del_recall_lru; later laundromat traversal is a classic slab UAF that can be groomed/reallocated to disclose arbitrary kernel memory.\nI:H - The same freed nfs4_delegation object remains on del_recall_lru so laundromat list operations write into attacker-reclaimable heap, yielding an arbitrary-write / control-flow hijack primitive.\nA:H - Use-after-free and list corruption of del_recall_lru reliably cause kernel oops/panic in the laundromat thread, fully disrupting availability of the NFS server host."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/nfsd/nfs4state.c"], "versions": [{"version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "04a8d07f3d58308b92630045560799a3faa3ebce", "status": "affected", "versionType": "git"}, {"version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "348714018139c39533c55661a0c7c990671396b4", "status": "affected", "versionType": "git"}, {"version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "33645d3e22720cac1e4548f8fef57bf0649536ee", "status": "affected", "versionType": "git"}, {"version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "2becaa990b93cbd2928292c0b669d3abb6cf06d4", "status": "affected", "versionType": "git"}, {"version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "e0759696de6851d7536efddfdd2dfed4c4df1f09", 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no victim user or administrator action on the server is required.\nS:U - The use-after-free corrupts kernel slab memory (nfs4_delegation on del_recall_lru) within the host nfsd security authority and does not cross a VM, IOMMU, or other separate boundary.\nC:H - The unhashed delegation is freed while still linked on del_recall_lru; later laundromat traversal is a classic slab UAF that can be groomed/reallocated to disclose arbitrary kernel memory.\nI:H - The same freed nfs4_delegation object remains on del_recall_lru so laundromat list operations write into attacker-reclaimable heap, yielding an arbitrary-write / control-flow hijack primitive.\nA:H - Use-after-free and list corruption of del_recall_lru reliably cause kernel oops/panic in the laundromat thread, fully disrupting availability of the NFS server host."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "04a8d07f3d58308b92630045560799a3faa3ebce", "versionType": "git"}, {"status": "affected", "version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "348714018139c39533c55661a0c7c990671396b4", "versionType": "git"}, {"status": "affected", "version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "33645d3e22720cac1e4548f8fef57bf0649536ee", "versionType": "git"}, {"status": "affected", "version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "2becaa990b93cbd2928292c0b669d3abb6cf06d4", "versionType": "git"}, {"status": "affected", "version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "e0759696de6851d7536efddfdd2dfed4c4df1f09", "versionType": "git"}, {"status": "affected", "version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "eeb0711801f5e19ef654371b627682aed3b11373", "versionType": "git"}, {"status": "affected", "version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "148c816f10fd11df27ca6a9b3238cdd42fa72cd3", "versionType": "git"}, {"status": "affected", "version": "dff1399f8addf7129c49bb2227469da79cc30b47", "lessThan": "548ec0805c399c65ed66c6641be467f717833ab5", "versionType": "git"}], "programFiles": ["fs/nfsd/nfs4state.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "3.17"}, {"status": "unaffected", "version": "0", "lessThan": "3.17", "versionType": "semver"}, {"status": "unaffected", "version": "4.4.296", "versionType": "semver", "lessThanOrEqual": "4.4.*"}, {"status": "unaffected", "version": "4.9.294", "versionType": "semver", "lessThanOrEqual": "4.9.*"}, {"status": "unaffected", "version": "4.14.259", "versionType": "semver", "lessThanOrEqual": "4.14.*"}, {"status": "unaffected", "version": "4.19.222", "versionType": "semver", "lessThanOrEqual": "4.19.*"}, {"status": "unaffected", "version": "5.4.168", "versionType": "semver", "lessThanOrEqual": "5.4.*"}, {"status": "unaffected", "version": "5.10.85", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.8", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "5.16", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["fs/nfsd/nfs4state.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/04a8d07f3d58308b92630045560799a3faa3ebce"}, {"url": "https://git.kernel.org/stable/c/348714018139c39533c55661a0c7c990671396b4"}, {"url": "https://git.kernel.org/stable/c/33645d3e22720cac1e4548f8fef57bf0649536ee"}, {"url": "https://git.kernel.org/stable/c/2becaa990b93cbd2928292c0b669d3abb6cf06d4"}, {"url": "https://git.kernel.org/stable/c/e0759696de6851d7536efddfdd2dfed4c4df1f09"}, {"url": "https://git.kernel.org/stable/c/eeb0711801f5e19ef654371b627682aed3b11373"}, {"url": "https://git.kernel.org/stable/c/148c816f10fd11df27ca6a9b3238cdd42fa72cd3"}, {"url": "https://git.kernel.org/stable/c/548ec0805c399c65ed66c6641be467f717833ab5"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix use-after-free due to delegation race\n\nA delegation break could arrive as soon as we've called vfs_setlease. A\ndelegation break runs a callback which immediately (in\nnfsd4_cb_recall_prepare) adds the delegation to del_recall_lru. If we\nthen exit nfs4_set_delegation without hashing the delegation, it will be\nfreed as soon as the callback is done with it, without ever being\nremoved from del_recall_lru.\n\nSymptoms show up later as use-after-free or list corruption warnings,\nusually in the laundromat thread.\n\nI suspect aba2072f4523 \"nfsd: grant read delegations to clients holding\nwrites\" made this bug easier to hit, but I looked as far back as v3.0\nand it looks to me it already had the same problem. So I'm not sure\nwhere the bug was introduced; it may have been there from the beginning."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "4.4.296", "versionStartIncluding": "3.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "4.9.294", "versionStartIncluding": "3.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "4.14.259", "versionStartIncluding": "3.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "4.19.222", "versionStartIncluding": "3.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.4.168", "versionStartIncluding": "3.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.85", "versionStartIncluding": "3.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15.8", "versionStartIncluding": "3.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.16", "versionStartIncluding": "3.17"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:48:10.240Z"}}}, "cveMetadata": {"cveId": "CVE-2021-47506", "state": "PUBLISHED", "dateUpdated": "2026-08-05T08:48:10.240Z", "dateReserved": "2024-05-22T06:20:56.205Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2024-05-24T15:01:52.746Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

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"versionType": "semver"}, {"lessThanOrEqual": "4.14.*", "status": "unaffected", "version": "4.14.259", "versionType": "semver"}, {"lessThanOrEqual": "4.19.*", "status": "unaffected", "version": "4.19.222", "versionType": "semver"}, {"lessThanOrEqual": "5.4.*", "status": "unaffected", "version": "5.4.168", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.85", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.8", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "5.16", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "1FF3BCF2-4788-45E7-BDAC-845DEBF8922F", "versionEndExcluding": "4.4.296", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": 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"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "6664ACE2-F748-4AE5-B98B-58803B0B2C3E", "versionEndExcluding": "5.15.8", "versionStartIncluding": "5.11", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*", "matchCriteriaId": "E46C74C6-B76B-4C94-A6A4-FD2FFF62D644", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*", "matchCriteriaId": "60134C3A-06E4-48C1-B04F-2903732A4E56", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*", "matchCriteriaId": "0460DA88-8FE1-46A2-9DDA-1F1ABA552E71", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc4:*:*:*:*:*:*", "matchCriteriaId": "AF55383D-4DF2-45DC-93F7-571F4F978EAB", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix use-after-free due to delegation race\n\nA delegation break could arrive as soon as we've called vfs_setlease. A\ndelegation break runs a callback which immediately (in\nnfsd4_cb_recall_prepare) adds the delegation to del_recall_lru. If we\nthen exit nfs4_set_delegation without hashing the delegation, it will be\nfreed as soon as the callback is done with it, without ever being\nremoved from del_recall_lru.\n\nSymptoms show up later as use-after-free or list corruption warnings,\nusually in the laundromat thread.\n\nI suspect aba2072f4523 \"nfsd: grant read delegations to clients holding\nwrites\" made this bug easier to hit, but I looked as far back as v3.0\nand it looks to me it already had the same problem. So I'm not sure\nwhere the bug was introduced; it may have been there from the beginning."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: nfsd: corrige el use-after-free debido a la ejecuci\u00f3n de delegaci\u00f3n. Una interrupci\u00f3n de la delegaci\u00f3n podr\u00eda llegar tan pronto como hayamos llamado a vfs_setlease. Una interrupci\u00f3n de la delegaci\u00f3n ejecuta una devoluci\u00f3n de llamada que inmediatamente (en nfsd4_cb_recall_prepare) agrega la delegaci\u00f3n a del_recall_lru. Si luego salimos de nfs4_set_delegation sin aplicar hash a la delegaci\u00f3n, se liberar\u00e1 tan pronto como finalice la devoluci\u00f3n de llamada, sin eliminarse nunca de del_recall_lru. Los s\u00edntomas aparecen m\u00e1s tarde como advertencias de use-after-free o de corrupci\u00f3n en la lista, generalmente en el hilo de la lavander\u00eda. Sospecho que aba2072f4523 \"nfsd: otorgar delegaciones de lectura a clientes que tienen escrituras\" hizo que este error fuera m\u00e1s f\u00e1cil de corregir, pero mir\u00e9 hasta la versi\u00f3n 3.0 y me parece que ya ten\u00eda el mismo problema. Entonces no estoy seguro de d\u00f3nde se introdujo el error; puede que haya estado ah\u00ed desde el principio."}], "id": "CVE-2021-47506", "lastModified": "2026-08-04T10:17:06.590", "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-2021-47506", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2024-05-29T17:04:47.932390Z", "version": "2.0.3"}}]}, "published": "2024-05-24T15:15:11.197", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/04a8d07f3d58308b92630045560799a3faa3ebce"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/148c816f10fd11df27ca6a9b3238cdd42fa72cd3"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2becaa990b93cbd2928292c0b669d3abb6cf06d4"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/33645d3e22720cac1e4548f8fef57bf0649536ee"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/348714018139c39533c55661a0c7c990671396b4"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/548ec0805c399c65ed66c6641be467f717833ab5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/e0759696de6851d7536efddfdd2dfed4c4df1f09"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/eeb0711801f5e19ef654371b627682aed3b11373"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/04a8d07f3d58308b92630045560799a3faa3ebce"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/148c816f10fd11df27ca6a9b3238cdd42fa72cd3"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2becaa990b93cbd2928292c0b669d3abb6cf06d4"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/33645d3e22720cac1e4548f8fef57bf0649536ee"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/348714018139c39533c55661a0c7c990671396b4"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/548ec0805c399c65ed66c6641be467f717833ab5"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/e0759696de6851d7536efddfdd2dfed4c4df1f09"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/eeb0711801f5e19ef654371b627682aed3b11373"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: nfsd: fix use-after-free due to delegation race", "id": "2283447", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2283447"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/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:\nnfsd: fix use-after-free due to delegation race\nA delegation break could arrive as soon as we've called vfs_setlease. A\ndelegation break runs a callback which immediately (in\nnfsd4_cb_recall_prepare) adds the delegation to del_recall_lru. If we\nthen exit nfs4_set_delegation without hashing the delegation, it will be\nfreed as soon as the callback is done with it, without ever being\nremoved from del_recall_lru.\nSymptoms show up later as use-after-free or list corruption warnings,\nusually in the laundromat thread.\nI suspect aba2072f4523 \"nfsd: grant read delegations to clients holding\nwrites\" made this bug easier to hit, but I looked as far back as v3.0\nand it looks to me it already had the same problem. So I'm not sure\nwhere the bug was introduced; it may have been there from the beginning."], "name": "CVE-2021-47506", "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": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "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": "2024-05-24T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-47506\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47506\nhttps://lore.kernel.org/linux-cve-announce/2024052452-CVE-2021-47506-c143@gregkh/T"], "threat_severity": "Moderate"}

{}