{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2021-47049", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-02-27T18:42:55.971Z", "datePublished": "2024-02-28T08:13:52.168Z", "dateUpdated": "2026-08-05T08:45:44.180Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:45:44.180Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nDrivers: hv: vmbus: Use after free in __vmbus_open()\n\nThe \"open_info\" variable is added to the &vmbus_connection.chn_msg_list,\nbut the error handling frees \"open_info\" without removing it from the\nlist. This will result in a use after free. First remove it from the\nlist, and then free it." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.4, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bug is reached only over the Hyper-V guest VMBus path (__vmbus_open during channel open after a host offer/rescind), which is local hypervisor IPC rather than an IP network or physical bus attack surface.\nAC:L - A malicious Hyper-V host fully controls CHANNELMSG_OFFERCHANNEL and CHANNELMSG_RESCIND_CHANNELOFFER timing relative to guest __vmbus_open(), so it can deterministically hit the rescinded-channel error path after open_info is linked onto chn_msg_list.\nPR:N - No privileges inside the guest are required; rescind/open messages are accepted from the Hyper-V parent over VMBus with no guest authentication, matching the untrusted-host/CoCo threat model used for similar vmbus bugs.\nUI:N - Channel probe/open and rescind handling run automatically in kernel workqueues when the host sends VMBus messages; no victim user action is required.\nS:U - The UAF corrupts guest-kernel heap state (chn_msg_list / vmbus_channel_msginfo) within the same guest OS security authority; it is not a guest-to-host escape.\nC:H - Use-after-free of open_info on a globally walked list enables heap reuse and arbitrary read primitives against kernel memory.\nI:H - The same UAF is exploitable for heap spraying and control-flow hijacking / arbitrary write in the guest kernel.\nA:H - Any subsequent chn_msg_list walk over the dangling entry can oops/panic the guest kernel even without a full exploit." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/hv/channel.c" ], "versions": [ { "version": "6f3d791f300618caf82a2be0c27456edd76d5164", "lessThan": "d5c7b42c9f56ca46b286daa537d181bd7f69214f", "status": "affected", "versionType": "git" }, { "version": "6f3d791f300618caf82a2be0c27456edd76d5164", "lessThan": "f37dd5d1b5d38a79a4f7b8dd7bbb705505f05560", "status": "affected", "versionType": "git" }, { "version": "6f3d791f300618caf82a2be0c27456edd76d5164", "lessThan": "2728f289b3270b0e273292b46c534421a33bbfd5", "status": "affected", "versionType": "git" }, { "version": "6f3d791f300618caf82a2be0c27456edd76d5164", "lessThan": "3e9bf43f7f7a46f21ec071cb47be92d0874c48da", "status": "affected", "versionType": "git" }, { "version": "6b32d45bd59982751beb8220e442b40b2706647f", "status": "affected", "versionType": "git" }, { "version": "4.13.9", "lessThan": "4.14", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/hv/channel.c" ], "versions": [ { "version": "4.14", "status": "affected" }, { "version": "0", "lessThan": "4.14", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.37", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.11.21", "lessThanOrEqual": "5.11.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.12.4", "lessThanOrEqual": "5.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.13", "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": "4.14", "versionEndExcluding": "5.10.37" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "5.11.21" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "5.12.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.14", "versionEndExcluding": "5.13" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13.9" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/d5c7b42c9f56ca46b286daa537d181bd7f69214f" }, { "url": "https://git.kernel.org/stable/c/f37dd5d1b5d38a79a4f7b8dd7bbb705505f05560" }, { "url": "https://git.kernel.org/stable/c/2728f289b3270b0e273292b46c534421a33bbfd5" }, { "url": "https://git.kernel.org/stable/c/3e9bf43f7f7a46f21ec071cb47be92d0874c48da" } ], "title": "Drivers: hv: vmbus: Use after free in __vmbus_open()", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T05:24:39.572Z" }, "title": "CVE Program Container", "references": [ { "url": "https://git.kernel.org/stable/c/d5c7b42c9f56ca46b286daa537d181bd7f69214f", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/f37dd5d1b5d38a79a4f7b8dd7bbb705505f05560", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/2728f289b3270b0e273292b46c534421a33bbfd5", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/3e9bf43f7f7a46f21ec071cb47be92d0874c48da", "tags": [ "x_transferred" ] } ] }, { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2024-08-08T18:59:39.474038Z", "id": "CVE-2021-47049", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-08-08T18:59:54.282Z" } } ] } }