Files
vuln-cve/data/2021/46xxx/CVE-2021-46993.json
T

275 lines
13 KiB
JSON
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
{
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"cveMetadata": {
"cveId": "CVE-2021-46993",
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"state": "PUBLISHED",
"assignerShortName": "Linux",
"dateReserved": "2024-02-27T18:42:55.949Z",
"datePublished": "2024-02-28T08:13:18.494Z",
"dateUpdated": "2026-08-05T08:45:26.827Z"
},
"containers": {
"cna": {
"providerMetadata": {
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux",
"dateUpdated": "2026-08-05T08:45:26.827Z"
},
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched: Fix out-of-bound access in uclamp\n\nUtil-clamp places tasks in different buckets based on their clamp values\nfor performance reasons. However, the size of buckets is currently\ncomputed using a rounding division, which can lead to an off-by-one\nerror in some configurations.\n\nFor instance, with 20 buckets, the bucket size will be 1024/20=51. A\ntask with a clamp of 1024 will be mapped to bucket id 1024/51=20. Sadly,\ncorrect indexes are in range [0,19], hence leading to an out of bound\nmemory access.\n\nClamp the bucket id to fix the issue."
}
],
"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 reached via the local sched_setattr syscall when a task sets util-clamp attributes; it is not reachable from the network stack or remote protocol handlers.\nAC:L - On the primary uclamp deployment (Android GKI with UCLAMP_BUCKETS_COUNT=20), setting clamp value 1024 reliably maps to out-of-range bucket_id 20 with no race or attacker-uncontrollable condition.\nPR:L - An unprivileged process can set its own sched_util_min/max through sched_setattr; __sched_setscheduler does not require CAP_SYS_NICE for UTIL_CLAMP on a same-owner fair-policy task.\nUI:N - Exploitation requires only the attacker’s own syscalls; no victim action such as opening a file or mounting a filesystem is needed.\nS:U - The corruption stays within the host kernel’s scheduling authority and does not cross a VM, IOMMU, or other security boundary.\nC:H - The out-of-bounds bucket access reads and writes adjacent per-CPU runqueue memory (including into cfs_rq), which can be leveraged for kernel information disclosure under the memory-corruption guidance.\nI:H - uclamp_rq_inc_id/dec_id perform out-of-bounds writes (tasks++/value assignment) that, for UCLAMP_MAX, land on uclamp_flags and the start of cfs_rq, enabling scheduler-state corruption and control-flow impact.\nA:H - Corrupting runqueue uclamp/cfs state can cause kernel warnings, oopses, or hangs, as seen when the bug was found via SCHED_WARN_ON on Android."
}
]
}
],
"affected": [
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"kernel/sched/core.c"
],
"versions": [
{
"version": "69842cba9ace84849bb9b8edcdf2cefccd97901c",
"lessThan": "687f523c134b7f0bd040ee1230f6d17990d54172",
"status": "affected",
"versionType": "git"
},
{
"version": "69842cba9ace84849bb9b8edcdf2cefccd97901c",
"lessThan": "f7347c85490b92dd144fa1fba9e1eca501656ab3",
"status": "affected",
"versionType": "git"
},
{
"version": "69842cba9ace84849bb9b8edcdf2cefccd97901c",
"lessThan": "3da3f804b82a0a382d523a21acf4cf3bb35f936d",
"status": "affected",
"versionType": "git"
},
{
"version": "69842cba9ace84849bb9b8edcdf2cefccd97901c",
"lessThan": "42ee47c7e3569d9a0e2cb5053c496d97d380472f",
"status": "affected",
"versionType": "git"
},
{
"version": "69842cba9ace84849bb9b8edcdf2cefccd97901c",
"lessThan": "6d2f8909a5fabb73fe2a63918117943986c39b6c",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"kernel/sched/core.c"
],
"versions": [
{
"version": "5.3",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.3",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.4.120",
"lessThanOrEqual": "5.4.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.10.38",
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.11.22",
"lessThanOrEqual": "5.11.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.12.5",
"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": "5.3",
"versionEndExcluding": "5.4.120"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.3",
"versionEndExcluding": "5.10.38"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.3",
"versionEndExcluding": "5.11.22"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.3",
"versionEndExcluding": "5.12.5"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.3",
"versionEndExcluding": "5.13"
}
]
}
]
}
],
"references": [
{
"url": "https://git.kernel.org/stable/c/687f523c134b7f0bd040ee1230f6d17990d54172"
},
{
"url": "https://git.kernel.org/stable/c/f7347c85490b92dd144fa1fba9e1eca501656ab3"
},
{
"url": "https://git.kernel.org/stable/c/3da3f804b82a0a382d523a21acf4cf3bb35f936d"
},
{
"url": "https://git.kernel.org/stable/c/42ee47c7e3569d9a0e2cb5053c496d97d380472f"
},
{
"url": "https://git.kernel.org/stable/c/6d2f8909a5fabb73fe2a63918117943986c39b6c"
}
],
"title": "sched: Fix out-of-bound access in uclamp",
"x_generator": {
"engine": "bippy-1.2.0"
}
},
"adp": [
{
"providerMetadata": {
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE",
"dateUpdated": "2024-08-04T05:24:37.912Z"
},
"title": "CVE Program Container",
"references": [
{
"url": "https://git.kernel.org/stable/c/687f523c134b7f0bd040ee1230f6d17990d54172",
"tags": [
"x_transferred"
]
},
{
"url": "https://git.kernel.org/stable/c/f7347c85490b92dd144fa1fba9e1eca501656ab3",
"tags": [
"x_transferred"
]
},
{
"url": "https://git.kernel.org/stable/c/3da3f804b82a0a382d523a21acf4cf3bb35f936d",
"tags": [
"x_transferred"
]
},
{
"url": "https://git.kernel.org/stable/c/42ee47c7e3569d9a0e2cb5053c496d97d380472f",
"tags": [
"x_transferred"
]
},
{
"url": "https://git.kernel.org/stable/c/6d2f8909a5fabb73fe2a63918117943986c39b6c",
"tags": [
"x_transferred"
]
}
]
},
{
"metrics": [
{
"other": {
"type": "ssvc",
"content": {
"id": "CVE-2021-46993",
"role": "CISA Coordinator",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2024-09-10T16:01:01.662746Z"
}
}
}
],
"title": "CISA ADP Vulnrichment",
"providerMetadata": {
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP",
"dateUpdated": "2024-09-11T17:33:38.812Z"
}
}
]
}
}