CVE-2021-47600 (GCVE-0-2021-47600)
Vulnerability from cvelistv5 – Published: 2024-06-19 14:54 – Updated: 2026-08-05 08:48
VLAI
EPSS
VEX
Title
dm btree remove: fix use after free in rebalance_children()
Summary
In the Linux kernel, the following vulnerability has been resolved:
dm btree remove: fix use after free in rebalance_children()
Move dm_tm_unlock() after dm_tm_dec().
Severity
7.8 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-06-20 17:58 UTC
Assigner
References
8 references
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 , < a48f6a2bf33734ec5669ee03067dfb6c5b4818d6
(git)
Affected: 3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 , < 66ea642af6fd4eacb5d0271a922130fcf8700424 (git) Affected: 3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 , < b03abd0aa09c05099f537cb05b8460c4298f0861 (git) Affected: 3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 , < 293f957be5e39720778fb1851ced7f5fba6d51c3 (git) Affected: 3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 , < 501ecd90efdc9b2edc6c28852ecd098a4adf8f00 (git) Affected: 3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 , < 0e21e6cd5eebfc929ac5fa3b97ca2d4ace3cb6a3 (git) Affected: 3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 , < 607beb420b3fe23b948a9bf447d993521a02fbbb (git) Affected: 3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 , < 1b8d2789dad0005fd5e7d35dab26a8e1203fb6da (git) |
guessed | |
| Linux | Linux |
Affected:
3.2
Unaffected: 0 , < 3.2 (semver) Unaffected: 4.4.296 , ≤ 4.4.* (semver) Unaffected: 4.9.294 , ≤ 4.9.* (semver) Unaffected: 4.14.259 , ≤ 4.14.* (semver) Unaffected: 4.19.222 , ≤ 4.19.* (semver) Unaffected: 5.4.168 , ≤ 5.4.* (semver) Unaffected: 5.10.88 , ≤ 5.10.* (semver) Unaffected: 5.15.11 , ≤ 5.15.* (semver) Unaffected: 5.16 , ≤ * (original_commit_for_fix) |
guessed |
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2021-47600",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2024-06-20T17:58:48.172185Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2024-06-20T18:07:48.062Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
},
{
"providerMetadata": {
"dateUpdated": "2024-08-04T05:47:40.382Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/a48f6a2bf33734ec5669ee03067dfb6c5b4818d6"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/66ea642af6fd4eacb5d0271a922130fcf8700424"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/b03abd0aa09c05099f537cb05b8460c4298f0861"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/293f957be5e39720778fb1851ced7f5fba6d51c3"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/501ecd90efdc9b2edc6c28852ecd098a4adf8f00"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/0e21e6cd5eebfc929ac5fa3b97ca2d4ace3cb6a3"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/607beb420b3fe23b948a9bf447d993521a02fbbb"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/1b8d2789dad0005fd5e7d35dab26a8e1203fb6da"
}
],
"title": "CVE Program Container"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/md/persistent-data/dm-btree-remove.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "a48f6a2bf33734ec5669ee03067dfb6c5b4818d6",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "66ea642af6fd4eacb5d0271a922130fcf8700424",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "b03abd0aa09c05099f537cb05b8460c4298f0861",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "293f957be5e39720778fb1851ced7f5fba6d51c3",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "501ecd90efdc9b2edc6c28852ecd098a4adf8f00",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "0e21e6cd5eebfc929ac5fa3b97ca2d4ace3cb6a3",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "607beb420b3fe23b948a9bf447d993521a02fbbb",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "1b8d2789dad0005fd5e7d35dab26a8e1203fb6da",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/md/persistent-data/dm-btree-remove.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "3.2"
},
{
"lessThan": "3.2",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "4.4.*",
"status": "unaffected",
"version": "4.4.296",
"versionType": "semver"
},
{
"lessThanOrEqual": "4.9.*",
"status": "unaffected",
"version": "4.9.294",
"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": "5.10.88",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.11",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "5.16",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "4.4.296",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "4.9.294",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "4.14.259",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "4.19.222",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.4.168",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.10.88",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.15.11",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.16",
"versionStartIncluding": "3.2",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm btree remove: fix use after free in rebalance_children()\n\nMove dm_tm_unlock() after dm_tm_dec()."
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 7.8,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The UAF is in dm-btree rebalance_children(), reached via local dm-thin metadata updates (discard \u2192 dm_thin_remove_range \u2192 dm_btree_remove/remove_leaves) or CAP_SYS_ADMIN dm-ioctl pool messages, not via network or adjacent protocols.\nAC:L - An attacker who can discard/unmap on a thin volume fully drives btree shrinkage into the single-child collapse path where unlock precedes dm_block_location(); no conditions outside attacker control are required, and UAFs are AC:L per guidance.\nPR:L - On hosts already using dm-thin/LVM thin pools, an unprivileged user with access to a thin-backed filesystem or device can issue discards (e.g. deletes under discard mounts or BLKDISCARD) that hit this path; creating the pool needs CAP_SYS_ADMIN but is a deployment precondition.\nUI:N - The attacker triggers the vulnerable remove/rebalance path themselves through their own I/O or ioctls; no separate victim action is required.\nS:U - This is a host-kernel heap use-after-free within the same OS security authority and does not cross a VM, IOMMU, or sandbox boundary.\nC:H - Unlocking the child block then reading dm_block_location(child) is a use-after-free on the bufio buffer; reclaim/spray of that object enables arbitrary kernel memory disclosure.\nI:H - The UAF can feed an attacker-controlled block number into dm_tm_dec(), corrupting the space map and yielding heap/metadata corruption primitives exploitable for arbitrary write and control-flow hijack.\nA:H - Any use-after-free can oops/panic the kernel (KASAN UAF or invalid access after reclaim), fully impacting availability even without successful code execution."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-05T08:48:32.894Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/a48f6a2bf33734ec5669ee03067dfb6c5b4818d6"
},
{
"url": "https://git.kernel.org/stable/c/66ea642af6fd4eacb5d0271a922130fcf8700424"
},
{
"url": "https://git.kernel.org/stable/c/b03abd0aa09c05099f537cb05b8460c4298f0861"
},
{
"url": "https://git.kernel.org/stable/c/293f957be5e39720778fb1851ced7f5fba6d51c3"
},
{
"url": "https://git.kernel.org/stable/c/501ecd90efdc9b2edc6c28852ecd098a4adf8f00"
},
{
"url": "https://git.kernel.org/stable/c/0e21e6cd5eebfc929ac5fa3b97ca2d4ace3cb6a3"
},
{
"url": "https://git.kernel.org/stable/c/607beb420b3fe23b948a9bf447d993521a02fbbb"
},
{
"url": "https://git.kernel.org/stable/c/1b8d2789dad0005fd5e7d35dab26a8e1203fb6da"
}
],
"title": "dm btree remove: fix use after free in rebalance_children()",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2021-47600",
"datePublished": "2024-06-19T14:54:00.981Z",
"dateReserved": "2024-05-24T15:11:00.736Z",
"dateUpdated": "2026-08-05T08:48:32.894Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2021-47600",
"date": "2026-11-05",
"epss": "0.00273",
"percentile": "0.1983"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/md/persistent-data/dm-btree-remove.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "a48f6a2bf33734ec5669ee03067dfb6c5b4818d6",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "66ea642af6fd4eacb5d0271a922130fcf8700424",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "b03abd0aa09c05099f537cb05b8460c4298f0861",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "293f957be5e39720778fb1851ced7f5fba6d51c3",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "501ecd90efdc9b2edc6c28852ecd098a4adf8f00",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "0e21e6cd5eebfc929ac5fa3b97ca2d4ace3cb6a3",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "607beb420b3fe23b948a9bf447d993521a02fbbb",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "1b8d2789dad0005fd5e7d35dab26a8e1203fb6da",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/md/persistent-data/dm-btree-remove.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "3.2"
},
{
"lessThan": "3.2",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "4.4.*",
"status": "unaffected",
"version": "4.4.296",
"versionType": "semver"
},
{
"lessThanOrEqual": "4.9.*",
"status": "unaffected",
"version": "4.9.294",
"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": "5.10.88",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.11",
"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": "BEC14782-2EE3-4635-A927-91559E4F451C",
"versionEndExcluding": "4.9.294",
"versionStartIncluding": "4.5",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "390D64FF-1DB7-4DD1-ADEF-CE96BEA2607C",
"versionEndExcluding": "4.14.259",
"versionStartIncluding": "4.10",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "2D0D89BC-6CF8-4BFB-8C91-472348052528",
"versionEndExcluding": "4.19.222",
"versionStartIncluding": "4.15",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "195EBAA1-4CCE-4898-9351-F4A0DBCAA022",
"versionEndExcluding": "5.4.168",
"versionStartIncluding": "4.20",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "A657B2D0-5B9D-42BE-A3BF-228DBC1B057C",
"versionEndExcluding": "5.10.88",
"versionStartIncluding": "5.5",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "11274E95-438A-449A-B100-01B2B0046669",
"versionEndExcluding": "5.15.11",
"versionStartIncluding": "5.11",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm btree remove: fix use after free in rebalance_children()\n\nMove dm_tm_unlock() after dm_tm_dec()."
},
{
"lang": "es",
"value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: dm btree remove: corrige el use after free en rebalance_children() Mueve dm_tm_unlock() despu\u00e9s de dm_tm_dec()."
}
],
"id": "CVE-2021-47600",
"lastModified": "2026-08-04T10:17:10.300",
"metrics": {
"cvssMetricV31": [
{
"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": "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-2021-47600",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2024-06-20T17:58:48.172185Z",
"version": "2.0.3"
}
}
]
},
"published": "2024-06-19T15:15:54.567",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/0e21e6cd5eebfc929ac5fa3b97ca2d4ace3cb6a3"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/1b8d2789dad0005fd5e7d35dab26a8e1203fb6da"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/293f957be5e39720778fb1851ced7f5fba6d51c3"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/501ecd90efdc9b2edc6c28852ecd098a4adf8f00"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/607beb420b3fe23b948a9bf447d993521a02fbbb"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/66ea642af6fd4eacb5d0271a922130fcf8700424"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/a48f6a2bf33734ec5669ee03067dfb6c5b4818d6"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/b03abd0aa09c05099f537cb05b8460c4298f0861"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/0e21e6cd5eebfc929ac5fa3b97ca2d4ace3cb6a3"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/1b8d2789dad0005fd5e7d35dab26a8e1203fb6da"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/293f957be5e39720778fb1851ced7f5fba6d51c3"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/501ecd90efdc9b2edc6c28852ecd098a4adf8f00"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/607beb420b3fe23b948a9bf447d993521a02fbbb"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/66ea642af6fd4eacb5d0271a922130fcf8700424"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/a48f6a2bf33734ec5669ee03067dfb6c5b4818d6"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/b03abd0aa09c05099f537cb05b8460c4298f0861"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-416"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Low",
"current_release_date": "2026-10-30T01:26:10+00:00",
"cve": "CVE-2021-47600",
"id": "CVE-2021-47600",
"initial_release_date": "2021-01-01T00:00:00+00:00",
"product_status:fixed": "50",
"product_status:known_affected": "90",
"product_status:known_not_affected": "109",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: dm btree remove: fix use after free in rebalance_children()",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-47600.json",
"version": "3"
},
"vulnrichment": {
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-04T05:47:40.382Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/a48f6a2bf33734ec5669ee03067dfb6c5b4818d6"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/66ea642af6fd4eacb5d0271a922130fcf8700424"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/b03abd0aa09c05099f537cb05b8460c4298f0861"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/293f957be5e39720778fb1851ced7f5fba6d51c3"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/501ecd90efdc9b2edc6c28852ecd098a4adf8f00"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/0e21e6cd5eebfc929ac5fa3b97ca2d4ace3cb6a3"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/607beb420b3fe23b948a9bf447d993521a02fbbb"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/1b8d2789dad0005fd5e7d35dab26a8e1203fb6da"
}
],
"title": "CVE Program Container"
},
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2021-47600",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2024-06-20T17:58:48.172185Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2024-06-20T17:58:56.255Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/md/persistent-data/dm-btree-remove.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "a48f6a2bf33734ec5669ee03067dfb6c5b4818d6",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "66ea642af6fd4eacb5d0271a922130fcf8700424",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "b03abd0aa09c05099f537cb05b8460c4298f0861",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "293f957be5e39720778fb1851ced7f5fba6d51c3",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "501ecd90efdc9b2edc6c28852ecd098a4adf8f00",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "0e21e6cd5eebfc929ac5fa3b97ca2d4ace3cb6a3",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "607beb420b3fe23b948a9bf447d993521a02fbbb",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
},
{
"lessThan": "1b8d2789dad0005fd5e7d35dab26a8e1203fb6da",
"status": "affected",
"version": "3241b1d3e0aaafbfcd320f4d71ade629728cc4f4",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/md/persistent-data/dm-btree-remove.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "3.2"
},
{
"lessThan": "3.2",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "4.4.*",
"status": "unaffected",
"version": "4.4.296",
"versionType": "semver"
},
{
"lessThanOrEqual": "4.9.*",
"status": "unaffected",
"version": "4.9.294",
"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": "5.10.88",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.11",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "5.16",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "4.4.296",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "4.9.294",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "4.14.259",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "4.19.222",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.4.168",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.10.88",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.15.11",
"versionStartIncluding": "3.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.16",
"versionStartIncluding": "3.2",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm btree remove: fix use after free in rebalance_children()\n\nMove dm_tm_unlock() after dm_tm_dec()."
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 7.8,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The UAF is in dm-btree rebalance_children(), reached via local dm-thin metadata updates (discard \u2192 dm_thin_remove_range \u2192 dm_btree_remove/remove_leaves) or CAP_SYS_ADMIN dm-ioctl pool messages, not via network or adjacent protocols.\nAC:L - An attacker who can discard/unmap on a thin volume fully drives btree shrinkage into the single-child collapse path where unlock precedes dm_block_location(); no conditions outside attacker control are required, and UAFs are AC:L per guidance.\nPR:L - On hosts already using dm-thin/LVM thin pools, an unprivileged user with access to a thin-backed filesystem or device can issue discards (e.g. deletes under discard mounts or BLKDISCARD) that hit this path; creating the pool needs CAP_SYS_ADMIN but is a deployment precondition.\nUI:N - The attacker triggers the vulnerable remove/rebalance path themselves through their own I/O or ioctls; no separate victim action is required.\nS:U - This is a host-kernel heap use-after-free within the same OS security authority and does not cross a VM, IOMMU, or sandbox boundary.\nC:H - Unlocking the child block then reading dm_block_location(child) is a use-after-free on the bufio buffer; reclaim/spray of that object enables arbitrary kernel memory disclosure.\nI:H - The UAF can feed an attacker-controlled block number into dm_tm_dec(), corrupting the space map and yielding heap/metadata corruption primitives exploitable for arbitrary write and control-flow hijack.\nA:H - Any use-after-free can oops/panic the kernel (KASAN UAF or invalid access after reclaim), fully impacting availability even without successful code execution."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-05T08:48:32.894Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/a48f6a2bf33734ec5669ee03067dfb6c5b4818d6"
},
{
"url": "https://git.kernel.org/stable/c/66ea642af6fd4eacb5d0271a922130fcf8700424"
},
{
"url": "https://git.kernel.org/stable/c/b03abd0aa09c05099f537cb05b8460c4298f0861"
},
{
"url": "https://git.kernel.org/stable/c/293f957be5e39720778fb1851ced7f5fba6d51c3"
},
{
"url": "https://git.kernel.org/stable/c/501ecd90efdc9b2edc6c28852ecd098a4adf8f00"
},
{
"url": "https://git.kernel.org/stable/c/0e21e6cd5eebfc929ac5fa3b97ca2d4ace3cb6a3"
},
{
"url": "https://git.kernel.org/stable/c/607beb420b3fe23b948a9bf447d993521a02fbbb"
},
{
"url": "https://git.kernel.org/stable/c/1b8d2789dad0005fd5e7d35dab26a8e1203fb6da"
}
],
"title": "dm btree remove: fix use after free in rebalance_children()",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2021-47600",
"datePublished": "2024-06-19T14:54:00.981Z",
"dateReserved": "2024-05-24T15:11:00.736Z",
"dateUpdated": "2026-08-05T08:48:32.894Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
Loading timeline…
Loading…
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.