CVE-2026-72197 (GCVE-0-2026-72197)
Vulnerability from cvelistv5
Published
2026-08-15 05:53
Modified
2026-08-17 05:41
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: bound DeleteIndexEntryAllocation memmove length
In do_action()'s DeleteIndexEntryAllocation case, e->size comes
from an on-disk INDEX_BUFFER entry. When e->size makes
e + e->size point past hdr + hdr->used,
PtrOffset(e1, Add2Ptr(hdr, used)) returns a negative ptrdiff_t
that is silently cast to a quasi-infinite size_t when passed
to memmove(). The memmove then walks past the destination
buffer.
The sibling DeleteIndexEntryRoot case at fslog.c:3540-3543
already carries the corresponding guard:
if (PtrOffset(e1, Add2Ptr(hdr, used)) < esize ||
Add2Ptr(e, esize) > Add2Ptr(lrh, rec_len) ||
used + esize > le32_to_cpu(hdr->total)) {
goto dirty_vol;
}
Apply the same shape to the allocation-path case. Also reject
esize == 0: memmove(e, e, ...) is a no-op and leaves
hdr->used unchanged, hiding a malformed entry from the
existing check_index_header() walk.
Reproduced under UML+KASAN on mainline 8d90b09e6741 by
mounting a crafted NTFS image: the unguarded memmove takes a
length of 0xffffffffffffff00 and the kernel oopses in
memmove+0x81/0x1a0 on the do_action+0x36a2 frame.
[almaz.alexandrovich@paragon-software.com: clang-formatted the changes]
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Linux | Linux |
Version: b46acd6a6a627d876898e1c84d3f84902264b445 Version: b46acd6a6a627d876898e1c84d3f84902264b445 Version: b46acd6a6a627d876898e1c84d3f84902264b445 Version: b46acd6a6a627d876898e1c84d3f84902264b445 Version: b46acd6a6a627d876898e1c84d3f84902264b445 Version: b46acd6a6a627d876898e1c84d3f84902264b445 Version: b46acd6a6a627d876898e1c84d3f84902264b445 |
||
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"fs/ntfs3/fslog.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "c38ed2ab62fab75fd6d0fdc2bee540fbebc7b959",
"status": "affected",
"version": "b46acd6a6a627d876898e1c84d3f84902264b445",
"versionType": "git"
},
{
"lessThan": "b509b9613f20dc5b653d54bf78fab00d79cc43c8",
"status": "affected",
"version": "b46acd6a6a627d876898e1c84d3f84902264b445",
"versionType": "git"
},
{
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"status": "affected",
"version": "b46acd6a6a627d876898e1c84d3f84902264b445",
"versionType": "git"
},
{
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"status": "affected",
"version": "b46acd6a6a627d876898e1c84d3f84902264b445",
"versionType": "git"
},
{
"lessThan": "09fddd52c1b0cef2c086d61be8f3d5dc92e36565",
"status": "affected",
"version": "b46acd6a6a627d876898e1c84d3f84902264b445",
"versionType": "git"
},
{
"lessThan": "554700c65d398276cb00a8ef95f1d5e00b9eff93",
"status": "affected",
"version": "b46acd6a6a627d876898e1c84d3f84902264b445",
"versionType": "git"
},
{
"lessThan": "fc4626bb3656362de8b0ecd56605d47a19ec3518",
"status": "affected",
"version": "b46acd6a6a627d876898e1c84d3f84902264b445",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"fs/ntfs3/fslog.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.15"
},
{
"lessThan": "5.15",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.212",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.178",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.145",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.97",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.15.212",
"versionStartIncluding": "5.15",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.1.178",
"versionStartIncluding": "5.15",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.97",
"versionStartIncluding": "5.15",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.40",
"versionStartIncluding": "5.15",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1.5",
"versionStartIncluding": "5.15",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2",
"versionStartIncluding": "5.15",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: bound DeleteIndexEntryAllocation memmove length\n\nIn do_action()\u0027s DeleteIndexEntryAllocation case, e-\u003esize comes\nfrom an on-disk INDEX_BUFFER entry. When e-\u003esize makes\ne + e-\u003esize point past hdr + hdr-\u003eused,\nPtrOffset(e1, Add2Ptr(hdr, used)) returns a negative ptrdiff_t\nthat is silently cast to a quasi-infinite size_t when passed\nto memmove(). The memmove then walks past the destination\nbuffer.\n\nThe sibling DeleteIndexEntryRoot case at fslog.c:3540-3543\nalready carries the corresponding guard:\n\n\tif (PtrOffset(e1, Add2Ptr(hdr, used)) \u003c esize ||\n\t Add2Ptr(e, esize) \u003e Add2Ptr(lrh, rec_len) ||\n\t used + esize \u003e le32_to_cpu(hdr-\u003etotal)) {\n\t\tgoto dirty_vol;\n\t}\n\nApply the same shape to the allocation-path case. Also reject\nesize == 0: memmove(e, e, ...) is a no-op and leaves\nhdr-\u003eused unchanged, hiding a malformed entry from the\nexisting check_index_header() walk.\n\nReproduced under UML+KASAN on mainline 8d90b09e6741 by\nmounting a crafted NTFS image: the unguarded memmove takes a\nlength of 0xffffffffffffff00 and the kernel oopses in\nmemmove+0x81/0x1a0 on the do_action+0x36a2 frame.\n\n[almaz.alexandrovich@paragon-software.com: clang-formatted the changes]"
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 8.4,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - Reachable only by mounting attacker-controlled NTFS media via the local mount syscall path (path_mount\u2192ntfs_fill_super\u2192ntfs_loadlog_and_replay\u2192log_replay\u2192do_action); ntfs3 parses on-disk $LogFile redo records, not remote network packets.\nAC:L - The attacker fully controls crafted $LogFile DeleteIndexEntryAllocation redo data and INDEX_BUFFER entry sizes on disk, so the PtrOffset underflow to ~0xffffffffffffff00 and subsequent memmove OOB are deterministic with no race or uncontrollable layout preconditions.\nPR:N - No privileges on the target are required; exploitation only needs a malicious NTFS image presented to ntfs3 (USB/loop/NBD block device) that root, udisks2/systemd automount, or an image-handling service mounts, matching the kernel CNA model for crafted-filesystem bugs.\nUI:N - On desktops/kiosks/automotive systems where udisks2 or systemd automounts removable NTFS media, inserting or attaching the crafted image triggers log_replay during mount with no further deliberate victim action beyond routine media handling.\nS:U - The quasi-infinite memmove corrupts kernel heap memory within the host OS security authority during ntfs3 journal replay; this is standard kernel memory corruption, not a VM escape, IOMMU bypass, or other cross-boundary scope change.\nC:H - The unchecked memmove length (~0xffffffffffffff00) performs a massive out-of-bounds read from beyond the kmalloc INDEX_BUFFER scratch buffer, exposing adjacent slab/heap contents and satisfying OOB-read/arbitrary-disclosure guidance even though KASAN reports an oops in memmove.\nI:H - The same memmove writes far past the destination INDEX_BUFFER allocation in kernel heap, yielding a large out-of-bounds write primitive that can corrupt adjacent kernel objects and be leveraged for control-flow hijacking or privilege escalation.\nA:H - Reproduced by mounting a crafted NTFS image under UML+KASAN, the unbounded memmove oopses the kernel in memmove from do_action; such heap corruption reliably threatens panic/oops and full denial of service on mount."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-17T05:41:24.114Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/c38ed2ab62fab75fd6d0fdc2bee540fbebc7b959"
},
{
"url": "https://git.kernel.org/stable/c/b509b9613f20dc5b653d54bf78fab00d79cc43c8"
},
{
"url": "https://git.kernel.org/stable/c/4c8aac931c1cd70347961ba5157aa916448c6a25"
},
{
"url": "https://git.kernel.org/stable/c/f383aae59ec3994c14804f4191c59038b206be81"
},
{
"url": "https://git.kernel.org/stable/c/09fddd52c1b0cef2c086d61be8f3d5dc92e36565"
},
{
"url": "https://git.kernel.org/stable/c/554700c65d398276cb00a8ef95f1d5e00b9eff93"
},
{
"url": "https://git.kernel.org/stable/c/fc4626bb3656362de8b0ecd56605d47a19ec3518"
}
],
"title": "fs/ntfs3: bound DeleteIndexEntryAllocation memmove length",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-72197",
"datePublished": "2026-08-15T05:53:56.149Z",
"dateReserved": "2026-08-09T03:40:39.911Z",
"dateUpdated": "2026-08-17T05:41:24.114Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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