{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2021-47201", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-03-25T09:12:14.117Z", "datePublished": "2024-04-10T18:56:35.774Z", "dateUpdated": "2026-08-05T08:46:42.381Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:46:42.381Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niavf: free q_vectors before queues in iavf_disable_vf\n\niavf_free_queues() clears adapter->num_active_queues, which\niavf_free_q_vectors() relies on, so swap the order of these two function\ncalls in iavf_disable_vf(). This resolves a panic encountered when the\ninterface is disabled and then later brought up again after PF\ncommunication is restored." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bug is in the iavf VF driver’s local reset/disable path (iavf_reset_task → iavf_disable_vf → iavf_free_q_vectors), reached via local netdev operations such as MTU/ethtool-driven resets or PF-reset handling—not by processing remote packets.\nAC:L - Once iavf_disable_vf runs, freeing q_vectors without netif_napi_del is fully deterministic with no race to win. A local actor can repeatedly schedule VF resets, and in the worst reasonable SR-IOV deployment PF communication failures/restoration (the commit’s own scenario) make this path reachable under attacker-driven reset pressure.\nPR:L - Triggering the reset/reopen path only requires CAP_NET_ADMIN in the netns that owns the VF (e.g. ip link set mtu / ifup). SR-IOV VFs are routinely delegated into tenant/container netnses where that capability is available via user namespaces without init-namespace root.\nUI:N - The attacker schedules resets and can bring the interface back up after PF communication is restored (or recovery proceeds via the watchdog); no separate victim action is required.\nS:U - The dangling napi_struct UAF corrupts kernel heap within the same OS authority that runs iavf. This is standard local kernel compromise/DoS, not a guest-to-host escape or IOMMU boundary bypass.\nC:H - q_vectors (containing napi_structs) are kfree’d while still linked on netdev->napi_list, leaving dangling pointers. An attacker can reoccupy the freed object; subsequent NAPI list walks read attacker-controlled state (as in the related iavf NAPI UAF CVE-2023-53556), enabling high confidentiality impact.\nI:H - Later napi_del/list walks perform list_del_rcu and related writes on the freed napi_struct, yielding arbitrary-write primitives via forged next/prev pointers, sufficient for control-flow hijacking under kernel UAF guidance.\nA:H - The commit documents a kernel panic when the interface is brought back up after PF communication is restored; any walk of the corrupted napi_list (reinit, free_netdev, etc.) can oops/panic the kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/intel/iavf/iavf_main.c" ], "versions": [ { "version": "65c7006f234c9ede887d468f595f259a5c5cc552", "lessThan": "926e8c83d4c1c2dac0026637eb0d492df876489e", "status": "affected", "versionType": "git" }, { "version": "65c7006f234c9ede887d468f595f259a5c5cc552", "lessThan": "78638b47132244e3934dc5dc79f6372d5ce8e98c", "status": "affected", "versionType": "git" }, { "version": "65c7006f234c9ede887d468f595f259a5c5cc552", "lessThan": "9ef6589cac9a8c47f5544ccdf4c498093733bb3f", "status": "affected", "versionType": "git" }, { "version": "65c7006f234c9ede887d468f595f259a5c5cc552", "lessThan": "89f22f129696ab53cfbc608e0a2184d0fea46ac1", "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/net/ethernet/intel/iavf/iavf_main.c" ], "versions": [ { "version": "4.13", "status": "affected" }, { "version": "0", "lessThan": "4.13", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.162", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.82", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.5", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.16", "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": "4.13", "versionEndExcluding": "5.4.162" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "5.10.82" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "5.15.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "5.16" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/926e8c83d4c1c2dac0026637eb0d492df876489e" }, { "url": "https://git.kernel.org/stable/c/78638b47132244e3934dc5dc79f6372d5ce8e98c" }, { "url": "https://git.kernel.org/stable/c/9ef6589cac9a8c47f5544ccdf4c498093733bb3f" }, { "url": "https://git.kernel.org/stable/c/89f22f129696ab53cfbc608e0a2184d0fea46ac1" } ], "title": "iavf: free q_vectors before queues in iavf_disable_vf", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "title": "CISA ADP Vulnrichment", "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2021-47201", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-04-10T19:51:02.253151Z" } } } ], "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-06-04T17:14:25.949Z" } }, { "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T05:32:07.396Z" }, "title": "CVE Program Container", "references": [ { "url": "https://git.kernel.org/stable/c/926e8c83d4c1c2dac0026637eb0d492df876489e", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/78638b47132244e3934dc5dc79f6372d5ce8e98c", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/9ef6589cac9a8c47f5544ccdf4c498093733bb3f", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/89f22f129696ab53cfbc608e0a2184d0fea46ac1", "tags": [ "x_transferred" ] } ] } ] } }