CVE-2026-72105 (GCVE-0-2026-72105)
Vulnerability from cvelistv5
Published
2026-08-15 05:52
Modified
2026-08-17 05:40
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
dm-log: fix a bitset_size overflow on 32bit machines
Commit c20e36b7631d ("dm log: fix out-of-bounds write due to
region_count overflow") made sure that region_count could fit in an
unsigned int. But the bitmap memory isn't allocated based on
region_count. It uses bitset_size (a size_t variable). The first step of
calculating bitset_size is to set it to region_count, rounded up to a
multiple of BITS_PER_LONG. If region_size is less than BITS_PER_LONG
smaller than UINT_MAX, it will get rounded up to 2^32. On a 32bit
architecture, this will make bitset_size wrap around to 0 and fail,
despite region_count being valid.
Since bitset_size gets divided by 8, it can hold any valid region_count.
It just needs a special case to handle the rollover. If it is 0, the
value rolled over, and bitset size should be set to the number of bytes
needed to hold 2^32 bits.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Linux | Linux |
Version: 44ab8875ae4a2842bde2d756bed195d375e0debb Version: defe483e47173768c227532694dc78cb65db5f09 Version: 3ec74da927b4e171a6fc0e77b1188ba4d019af51 Version: d4ac87567f86a55c3c92e9a5144dcd943a9772a1 Version: 12bd5b88e91a02785244ff1d20fb157e96e9cdc8 Version: b455903eed4558982be0811f5b7f44f6bbc4ff57 Version: c20e36b7631d83e7535877f08af8b0af72c44b1a Version: c20e36b7631d83e7535877f08af8b0af72c44b1a Version: 4ec8323b9f0764a14d532b1ae9b87f8a9fecb867 Version: 5.10.258 ≤ Version: 5.15.209 ≤ Version: 6.1.175 ≤ Version: 6.6.141 ≤ Version: 6.12.91 ≤ Version: 6.18.33 ≤ Version: 7.0.10 ≤ |
||
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/md/dm-log.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "cdc4ddf9db2cb79f4ab86b1a509b7ac21b0b6cf5",
"status": "affected",
"version": "44ab8875ae4a2842bde2d756bed195d375e0debb",
"versionType": "git"
},
{
"lessThan": "4b0de5a3ac1fd42acb0dc1f80ac5747e3287d723",
"status": "affected",
"version": "defe483e47173768c227532694dc78cb65db5f09",
"versionType": "git"
},
{
"lessThan": "567602fa72d57169365cbc589e0b8c3be900636d",
"status": "affected",
"version": "3ec74da927b4e171a6fc0e77b1188ba4d019af51",
"versionType": "git"
},
{
"lessThan": "d05e0edfecf5260e6dddd28b2f0cce02bfc6ed7a",
"status": "affected",
"version": "d4ac87567f86a55c3c92e9a5144dcd943a9772a1",
"versionType": "git"
},
{
"lessThan": "1c3412b584e1fb6c665ff33ba7259253bc0082cb",
"status": "affected",
"version": "12bd5b88e91a02785244ff1d20fb157e96e9cdc8",
"versionType": "git"
},
{
"lessThan": "e0b0163a65758ec3a2361ae1cea407898c27f21e",
"status": "affected",
"version": "b455903eed4558982be0811f5b7f44f6bbc4ff57",
"versionType": "git"
},
{
"lessThan": "79feb87ab2396d49b9b65e4bb815d33cc71cba47",
"status": "affected",
"version": "c20e36b7631d83e7535877f08af8b0af72c44b1a",
"versionType": "git"
},
{
"lessThan": "9743132a41f4d9d0e54c5f2adcb821b04796bab1",
"status": "affected",
"version": "c20e36b7631d83e7535877f08af8b0af72c44b1a",
"versionType": "git"
},
{
"status": "affected",
"version": "4ec8323b9f0764a14d532b1ae9b87f8a9fecb867",
"versionType": "git"
},
{
"lessThan": "5.10.261",
"status": "affected",
"version": "5.10.258",
"versionType": "semver"
},
{
"lessThan": "5.15.212",
"status": "affected",
"version": "5.15.209",
"versionType": "semver"
},
{
"lessThan": "6.1.178",
"status": "affected",
"version": "6.1.175",
"versionType": "semver"
},
{
"lessThan": "6.6.145",
"status": "affected",
"version": "6.6.141",
"versionType": "semver"
},
{
"lessThan": "6.12.97",
"status": "affected",
"version": "6.12.91",
"versionType": "semver"
},
{
"lessThan": "6.18.40",
"status": "affected",
"version": "6.18.33",
"versionType": "semver"
},
{
"lessThan": "7.1",
"status": "affected",
"version": "7.0.10",
"versionType": "semver"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/md/dm-log.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "7.1"
},
{
"lessThan": "7.1",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"version": "5.10.261",
"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": "5.10.261",
"versionStartIncluding": "5.10.258",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.15.212",
"versionStartIncluding": "5.15.209",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.1.178",
"versionStartIncluding": "6.1.175",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.6.145",
"versionStartIncluding": "6.6.141",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.97",
"versionStartIncluding": "6.12.91",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.40",
"versionStartIncluding": "6.18.33",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1.5",
"versionStartIncluding": "7.1",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2",
"versionStartIncluding": "7.1",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "7.0.10",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm-log: fix a bitset_size overflow on 32bit machines\n\nCommit c20e36b7631d (\"dm log: fix out-of-bounds write due to\nregion_count overflow\") made sure that region_count could fit in an\nunsigned int. But the bitmap memory isn\u0027t allocated based on\nregion_count. It uses bitset_size (a size_t variable). The first step of\ncalculating bitset_size is to set it to region_count, rounded up to a\nmultiple of BITS_PER_LONG. If region_size is less than BITS_PER_LONG\nsmaller than UINT_MAX, it will get rounded up to 2^32. On a 32bit\narchitecture, this will make bitset_size wrap around to 0 and fail,\ndespite region_count being valid.\n\nSince bitset_size gets divided by 8, it can hold any valid region_count.\nIt just needs a special case to handle the rollover. If it is 0, the\nvalue rolled over, and bitset size should be set to the number of bytes\nneeded to hold 2^32 bits."
}
],
"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 flaw is reached only via local Device Mapper ioctls on /dev/mapper/control (dmsetup table load creating a mirror with core/disk log); there is no network, wireless, or physical-bus receive path into create_log_context().\nAC:L - A CAP_SYS_ADMIN attacker fully controls mirror table length and region_size via dmsetup, deterministically forcing region_count into the UINT_MAX-30..UINT_MAX wrap range on 32-bit kernels without races or victim-specific heap layout.\nPR:L - DM control ioctls require CAP_SYS_ADMIN, which is obtainable inside an unprivileged user namespace per kernel CNA guidance; mirror/dm-log setup is not limited to init-namespace root on typical container-capable systems.\nUI:N - Exploitation requires only the attacker issuing dmsetup/ioctl to create or resume a mirror with crafted parameters; no separate victim action such as mounting a filesystem or opening a file is needed.\nS:U - Impact is kernel vmalloc heap corruption and privilege escalation within the host kernel; it does not cross a VM, hypervisor, or IOMMU security boundary.\nC:H - Wrapping bitset_size to zero undersizes clean_bits/sync_bits/recovering_bits versus lc-\u003eregion_count near UINT_MAX; subsequent log_test_bit/__set_bit_le calls during mirror I/O perform out-of-bounds reads of adjacent vmalloc heap memory.\nI:H - The same undersized bitmap sizing lets log_set_bit and log_clear_bit write far beyond the allocated bitset via region indices derived from dm mirror bios, corrupting adjacent kernel heap objects exploitable for arbitrary write or code execution.\nA:H - Identical dm-log bitset paths (e.g., core_in_sync calling log_test_bit) have been shown to kernel-crash with CR2 faults from out-of-bounds heap access; triggering this overflow causes oops, panic, or hang on affected 32-bit storage nodes."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-17T05:40:19.004Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/cdc4ddf9db2cb79f4ab86b1a509b7ac21b0b6cf5"
},
{
"url": "https://git.kernel.org/stable/c/4b0de5a3ac1fd42acb0dc1f80ac5747e3287d723"
},
{
"url": "https://git.kernel.org/stable/c/567602fa72d57169365cbc589e0b8c3be900636d"
},
{
"url": "https://git.kernel.org/stable/c/d05e0edfecf5260e6dddd28b2f0cce02bfc6ed7a"
},
{
"url": "https://git.kernel.org/stable/c/1c3412b584e1fb6c665ff33ba7259253bc0082cb"
},
{
"url": "https://git.kernel.org/stable/c/e0b0163a65758ec3a2361ae1cea407898c27f21e"
},
{
"url": "https://git.kernel.org/stable/c/79feb87ab2396d49b9b65e4bb815d33cc71cba47"
},
{
"url": "https://git.kernel.org/stable/c/9743132a41f4d9d0e54c5f2adcb821b04796bab1"
}
],
"title": "dm-log: fix a bitset_size overflow on 32bit machines",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-72105",
"datePublished": "2026-08-15T05:52:48.099Z",
"dateReserved": "2026-08-09T03:40:39.906Z",
"dateUpdated": "2026-08-17T05:40:19.004Z",
"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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