FKIE_CVE-2026-43303
Vulnerability from fkie_nvd - Published: 2026-05-08 14:16 - Updated: 2026-09-08 09:18
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved:
mm/page_alloc: clear page->private in free_pages_prepare()
Several subsystems (slub, shmem, ttm, etc.) use page->private but don't
clear it before freeing pages. When these pages are later allocated as
high-order pages and split via split_page(), tail pages retain stale
page->private values.
This causes a use-after-free in the swap subsystem. The swap code uses
page->private to track swap count continuations, assuming freshly
allocated pages have page->private == 0. When stale values are present,
swap_count_continued() incorrectly assumes the continuation list is valid
and iterates over uninitialized page->lru containing LIST_POISON values,
causing a crash:
KASAN: maybe wild-memory-access in range [0xdead000000000100-0xdead000000000107]
RIP: 0010:__do_sys_swapoff+0x1151/0x1860
Fix this by clearing page->private in free_pages_prepare(), ensuring all
freed pages have clean state regardless of previous use.
References
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| linux | linux_kernel | * | |
| linux | linux_kernel | * | |
| linux | linux_kernel | 5.18 | |
| linux | linux_kernel | 5.18 | |
| linux | linux_kernel | 5.18 | |
| linux | linux_kernel | 5.18 | |
| linux | linux_kernel | 5.18 | |
| linux | linux_kernel | 5.18 |
{
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"mm/page_alloc.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "e7790ab165713b79b1617ce659742ceb3a859d05",
"status": "affected",
"version": "3b8000ae185cb068adbda5f966a3835053c85fd4",
"versionType": "git"
},
{
"lessThan": "3edb8ebbf79b9016040e8f3421d723ae3d542b32",
"status": "affected",
"version": "3b8000ae185cb068adbda5f966a3835053c85fd4",
"versionType": "git"
},
{
"lessThan": "f9719e32a67b4b00b3c9b133e8b5ffa72a26b67b",
"status": "affected",
"version": "3b8000ae185cb068adbda5f966a3835053c85fd4",
"versionType": "git"
},
{
"lessThan": "23b82b7a26182ad840ae67d390d7ec9771e8c00f",
"status": "affected",
"version": "3b8000ae185cb068adbda5f966a3835053c85fd4",
"versionType": "git"
},
{
"lessThan": "d757c793853ec5483eb41ec2942c300b8fa720fb",
"status": "affected",
"version": "3b8000ae185cb068adbda5f966a3835053c85fd4",
"versionType": "git"
},
{
"lessThan": "ac1ea219590c09572ed5992dc233bbf7bb70fef9",
"status": "affected",
"version": "3b8000ae185cb068adbda5f966a3835053c85fd4",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"mm/page_alloc.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.18"
},
{
"lessThan": "5.18",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.176",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.143",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.93",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.16",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.19.*",
"status": "unaffected",
"version": "6.19.6",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.0",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"affectedData": [
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.6",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.6",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.6",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.6",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "*",
"status": "affected",
"version": "V3.1.6",
"versionType": "custom"
}
]
}
],
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "B1BE1177-E500-439D-B3E5-0E63F54C1BE6",
"versionEndExcluding": "6.18.16",
"versionStartIncluding": "5.18.1",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "373EEEDA-FAA1-4FB4-B6ED-DB4DD99DBE67",
"versionEndExcluding": "6.19.6",
"versionStartIncluding": "6.19",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:-:*:*:*:*:*:*",
"matchCriteriaId": "0384FA0A-DE99-48D7-84E3-46ED0C3B5E03",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc4:*:*:*:*:*:*",
"matchCriteriaId": "DA5F085D-52F3-4EE2-8353-455D1A6FE073",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc5:*:*:*:*:*:*",
"matchCriteriaId": "D6EE5B78-0D83-4715-893C-ABD69B49E7FC",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc6:*:*:*:*:*:*",
"matchCriteriaId": "EE723F14-047B-4FCF-B109-E0542EDFB063",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc7:*:*:*:*:*:*",
"matchCriteriaId": "2FCFCE58-5118-4D05-864E-C82CF20EABE5",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc9:*:*:*:*:*:*",
"matchCriteriaId": "9C3E5BC9-613C-4362-BF02-153A5BBFFB2F",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/page_alloc: clear page-\u003eprivate in free_pages_prepare()\n\nSeveral subsystems (slub, shmem, ttm, etc.) use page-\u003eprivate but don\u0027t\nclear it before freeing pages. When these pages are later allocated as\nhigh-order pages and split via split_page(), tail pages retain stale\npage-\u003eprivate values.\n\nThis causes a use-after-free in the swap subsystem. The swap code uses\npage-\u003eprivate to track swap count continuations, assuming freshly\nallocated pages have page-\u003eprivate == 0. When stale values are present,\nswap_count_continued() incorrectly assumes the continuation list is valid\nand iterates over uninitialized page-\u003elru containing LIST_POISON values,\ncausing a crash:\n\n KASAN: maybe wild-memory-access in range [0xdead000000000100-0xdead000000000107]\n RIP: 0010:__do_sys_swapoff+0x1151/0x1860\n\nFix this by clearing page-\u003eprivate in free_pages_prepare(), ensuring all\nfreed pages have clean state regardless of previous use."
}
],
"id": "CVE-2026-43303",
"lastModified": "2026-09-08T09:18:04.847",
"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"
}
]
},
"published": "2026-05-08T14:16:37.583",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/23b82b7a26182ad840ae67d390d7ec9771e8c00f"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/3edb8ebbf79b9016040e8f3421d723ae3d542b32"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/ac1ea219590c09572ed5992dc233bbf7bb70fef9"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/d757c793853ec5483eb41ec2942c300b8fa720fb"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/e7790ab165713b79b1617ce659742ceb3a859d05"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/f9719e32a67b4b00b3c9b133e8b5ffa72a26b67b"
},
{
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-416"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
Loading…
Loading…
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.
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.
Loading…