221 lines
11 KiB
JSON
221 lines
11 KiB
JSON
{
|
|
"dataType": "CVE_RECORD",
|
|
"dataVersion": "5.2",
|
|
"cveMetadata": {
|
|
"cveId": "CVE-2021-47111",
|
|
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
|
|
"state": "PUBLISHED",
|
|
"assignerShortName": "Linux",
|
|
"dateReserved": "2024-03-04T18:12:48.836Z",
|
|
"datePublished": "2024-03-15T20:14:19.898Z",
|
|
"dateUpdated": "2026-08-05T08:46:04.618Z"
|
|
},
|
|
"containers": {
|
|
"cna": {
|
|
"providerMetadata": {
|
|
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
|
|
"shortName": "Linux",
|
|
"dateUpdated": "2026-08-05T08:46:04.618Z"
|
|
},
|
|
"descriptions": [
|
|
{
|
|
"lang": "en",
|
|
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxen-netback: take a reference to the RX task thread\n\nDo this in order to prevent the task from being freed if the thread\nreturns (which can be triggered by the frontend) before the call to\nkthread_stop done as part of the backend tear down. Not taking the\nreference will lead to a use-after-free in that scenario. Such\nreference was taken before but dropped as part of the rework done in\n2ac061ce97f4.\n\nReintroduce the reference taking and add a comment this time\nexplaining why it's needed.\n\nThis is XSA-374 / CVE-2021-28691."
|
|
}
|
|
],
|
|
"metrics": [
|
|
{
|
|
"cvssV3_1": {
|
|
"version": "3.1",
|
|
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
|
|
"baseScore": 8.8,
|
|
"baseSeverity": "HIGH"
|
|
},
|
|
"scenarios": [
|
|
{
|
|
"lang": "en",
|
|
"value": "AV:L - The attack is carried out by a Xen guest through the PV netfront shared rings and event channels on the same host, not via remote network packets or physical device access.\nAC:L - The guest reliably triggers the bug by posting a malformed TX request (e.g. excess slots or cross-page offsets) to force the RX kthread to exit, then switching the frontend xenstore state to Closing/Closed to cause backend teardown and the UAF; both steps are fully attacker-controlled.\nPR:L - Exploitation requires a guest domain with a configured PV network frontend (typical cloud/tenant guest control), which is low privilege relative to Dom0 and does not require host-admin rights.\nUI:N - No victim user action is required; the guest alone can send the malformed frontend requests and drive the disconnect state change.\nS:C - This is a Xen guest-to-host escape: a DomU compromises Dom0 kernel memory via UAF in xen-netback, crossing the guest/host security boundary.\nC:H - Use-after-free of a host task_struct can be leveraged for arbitrary kernel memory disclosure; XSA-374 explicitly states information leaks cannot be ruled out.\nI:H - The same UAF enables heap reuse and control-flow hijacking in Dom0, and XSA-374 states privilege escalation cannot be ruled out.\nA:H - Calling kthread_stop() on the freed task_struct can crash or hang Dom0, which XSA-374 confirms as a host denial of service."
|
|
}
|
|
]
|
|
}
|
|
],
|
|
"affected": [
|
|
{
|
|
"product": "Linux",
|
|
"vendor": "Linux",
|
|
"defaultStatus": "unaffected",
|
|
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
|
|
"programFiles": [
|
|
"drivers/net/xen-netback/interface.c"
|
|
],
|
|
"versions": [
|
|
{
|
|
"version": "2ac061ce97f413bfbbdd768f7d2e0fda2e8170df",
|
|
"lessThan": "6b53db8c4c14b4e7256f058d202908b54a7b85b4",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "2ac061ce97f413bfbbdd768f7d2e0fda2e8170df",
|
|
"lessThan": "caec9bcaeb1a5f03f2d406305355c853af10c13e",
|
|
"status": "affected",
|
|
"versionType": "git"
|
|
},
|
|
{
|
|
"version": "2ac061ce97f413bfbbdd768f7d2e0fda2e8170df",
|
|
"lessThan": "107866a8eb0b664675a260f1ba0655010fac1e08",
|
|
"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/xen-netback/interface.c"
|
|
],
|
|
"versions": [
|
|
{
|
|
"version": "5.5",
|
|
"status": "affected"
|
|
},
|
|
{
|
|
"version": "0",
|
|
"lessThan": "5.5",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "5.10.43",
|
|
"lessThanOrEqual": "5.10.*",
|
|
"status": "unaffected",
|
|
"versionType": "semver"
|
|
},
|
|
{
|
|
"version": "5.12.10",
|
|
"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": "5.5",
|
|
"versionEndExcluding": "5.10.43"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "5.5",
|
|
"versionEndExcluding": "5.12.10"
|
|
},
|
|
{
|
|
"vulnerable": true,
|
|
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
|
|
"versionStartIncluding": "5.5",
|
|
"versionEndExcluding": "5.13"
|
|
}
|
|
]
|
|
}
|
|
]
|
|
}
|
|
],
|
|
"references": [
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/6b53db8c4c14b4e7256f058d202908b54a7b85b4"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/caec9bcaeb1a5f03f2d406305355c853af10c13e"
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/107866a8eb0b664675a260f1ba0655010fac1e08"
|
|
}
|
|
],
|
|
"title": "xen-netback: take a reference to the RX task thread",
|
|
"x_generator": {
|
|
"engine": "bippy-1.2.0"
|
|
}
|
|
},
|
|
"adp": [
|
|
{
|
|
"metrics": [
|
|
{
|
|
"other": {
|
|
"type": "ssvc",
|
|
"content": {
|
|
"timestamp": "2024-06-26T20:36:51.215407Z",
|
|
"id": "CVE-2021-47111",
|
|
"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": "2024-06-26T20:36:58.053Z"
|
|
}
|
|
},
|
|
{
|
|
"providerMetadata": {
|
|
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
|
|
"shortName": "CVE",
|
|
"dateUpdated": "2024-08-04T05:24:39.854Z"
|
|
},
|
|
"title": "CVE Program Container",
|
|
"references": [
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/6b53db8c4c14b4e7256f058d202908b54a7b85b4",
|
|
"tags": [
|
|
"x_transferred"
|
|
]
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/caec9bcaeb1a5f03f2d406305355c853af10c13e",
|
|
"tags": [
|
|
"x_transferred"
|
|
]
|
|
},
|
|
{
|
|
"url": "https://git.kernel.org/stable/c/107866a8eb0b664675a260f1ba0655010fac1e08",
|
|
"tags": [
|
|
"x_transferred"
|
|
]
|
|
}
|
|
]
|
|
}
|
|
]
|
|
}
|
|
} |