CVE-2026-89755

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-89755", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.763Z", "datePublished": "2026-09-11T19:46:58.295Z", "dateUpdated": "2026-11-06T17:14:58.290Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-11-06T17:14:58.290Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/migrate_device: clear stale mapping after freeing swapcache\n\n__migrate_device_pages() reads the folio mapping before calling\nfolio_free_swap(). When folio_free_swap() succeeds, the folio is removed\nfrom the swap cache, but the saved mapping still points to swap_space.\n\nPassing the stale mapping to folio_migrate_mapping() makes it use the\nmapped-folio path for a folio that is no longer in swapcache. It can then\noperate on swap_space.i_pages with invalid reference accounting,\neventually triggering a folio reference count BUG.\n\nAfter a successful split, nr still contains the number of pages in the\noriginal large folio, although each resulting page is now a separate\norder-0 folio. Reset nr to 1 so each split folio is processed separately,\nincluding its own swapcache removal and mapping lookup.\n\nRefresh the saved mapping after folio_free_swap() so the current folio\nstate is used during migration."}], "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 in __migrate_device_pages() on the migrate-to-device path (migrate_vma_pages), reached from local GPU HMM/SVM ioctls such as AMDKFD_IOC_SVM, DRM_NOUVEAU_SVM_BIND (DRM_RENDER_ALLOW), and Intel Xe drm_pagemap_migrate_to_devmem, not from network packets.\nAC:L - The attacker controls both preconditions: anonymous pages in their VMA, optionally kept in swapcache via pageout/swapin, then a migrate-to-VRAM ioctl. folio_free_swap() succeeds on locked mapped swapcache folios with swap count 0, which the attacker can arrange; no victim timing or uncontrollable layout is required.\nPR:L - Nouveau SVM bind is DRM_RENDER_ALLOW and KFD SVM/Xe pagemap paths have no capable() or DRM-master check. An unprivileged local user with typical render/video-group access to /dev/dri/renderD* or /dev/kfd on GPU systems can trigger the migration.\nUI:N - The attacker drives the whole sequence in their own process (anonymous mmap, optional madvise pageout, and GPU SVM migrate-to-device ioctls). No action by another user or administrator is required.\nS:U - Impact is host-kernel swap-cache and folio-refcount corruption, i.e. standard local privilege escalation in the same security authority, not a KVM/Xen guest-to-host escape or IOMMU/DMA boundary bypass.\nC:H - After folio_free_swap() the stale mapping still points at swap_space, so folio_migrate_mapping() xas_store()s a device-private folio into the global swap cache and underflows the source refcount; that UAF/type confusion of swap_space.i_pages yields an arbitrary kernel read primitive.\nI:H - The same xarray insertion and refcount underflow corrupt shared MM metadata (swap cache and folio references), which is exploitable for heap reuse and arbitrary kernel writes or control-flow hijack, not a bounded integrity change.\nA:H - Invalid reference accounting on swap_space.i_pages is documented to hit a folio reference-count BUG, and the resulting underflow/UAF also causes kernel oops or panic even without a completed exploit."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["mm/migrate_device.c"], "versions": [{"version": "df263d9a7dffee94ca5391120ee3b0587efa07f1", "lessThan": "92db780dd644590c751246187e1229d5ac2e5544", "status": "affected", "versionType": "git"}, {"version": "df263d9a7dffee94ca5391120ee3b0587efa07f1", "lessThan": "4fa91f7bbc4135240b67daac03fc17d9e180a331", "status": "affected", "versionType": "git"}, {"version": "df263d9a7dffee94ca5391120ee3b0587efa07f1", "lessThan": "c9c29481d5d4a985a57ece2090a324ba48e362a7", "status": "affected", "versionType": "git"}, {"version": "df263d9a7dffee94ca5391120ee3b0587efa07f1", "lessThan": "8ffedc6573a665cdc31ebe47eae7b32b78d0df83", "status": "affected", "versionType": "git"}, {"version": "df263d9a7dffee94ca5391120ee3b0587efa07f1", "lessThan": "34a00895d032a414830d41106a09329ae6c251b6", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["mm/migrate_device.c"], "versions": [{"version": "6.6", "status": "affected"}, {"version": "0", "lessThan": "6.6", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.111", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.61", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "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": "6.6", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.12.111"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.18.61"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "7.2.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/92db780dd644590c751246187e1229d5ac2e5544"}, {"url": "https://git.kernel.org/stable/c/4fa91f7bbc4135240b67daac03fc17d9e180a331"}, {"url": "https://git.kernel.org/stable/c/c9c29481d5d4a985a57ece2090a324ba48e362a7"}, {"url": "https://git.kernel.org/stable/c/8ffedc6573a665cdc31ebe47eae7b32b78d0df83"}, {"url": "https://git.kernel.org/stable/c/34a00895d032a414830d41106a09329ae6c251b6"}], "title": "mm/migrate_device: clear stale mapping after freeing swapcache", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["mm/migrate_device.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "92db780dd644590c751246187e1229d5ac2e5544", "status": "affected", "version": "df263d9a7dffee94ca5391120ee3b0587efa07f1", "versionType": "git"}, {"lessThan": "4fa91f7bbc4135240b67daac03fc17d9e180a331", "status": "affected", "version": "df263d9a7dffee94ca5391120ee3b0587efa07f1", "versionType": "git"}, {"lessThan": "c9c29481d5d4a985a57ece2090a324ba48e362a7", "status": "affected", "version": "df263d9a7dffee94ca5391120ee3b0587efa07f1", "versionType": "git"}, {"lessThan": "8ffedc6573a665cdc31ebe47eae7b32b78d0df83", "status": "affected", "version": "df263d9a7dffee94ca5391120ee3b0587efa07f1", "versionType": "git"}, {"lessThan": "34a00895d032a414830d41106a09329ae6c251b6", "status": "affected", "version": "df263d9a7dffee94ca5391120ee3b0587efa07f1", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["mm/migrate_device.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.6"}, {"lessThan": "6.6", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.160", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.111", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.61", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/migrate_device: clear stale mapping after freeing swapcache\n\n__migrate_device_pages() reads the folio mapping before calling\nfolio_free_swap(). When folio_free_swap() succeeds, the folio is removed\nfrom the swap cache, but the saved mapping still points to swap_space.\n\nPassing the stale mapping to folio_migrate_mapping() makes it use the\nmapped-folio path for a folio that is no longer in swapcache. It can then\noperate on swap_space.i_pages with invalid reference accounting,\neventually triggering a folio reference count BUG.\n\nAfter a successful split, nr still contains the number of pages in the\noriginal large folio, although each resulting page is now a separate\norder-0 folio. Reset nr to 1 so each split folio is processed separately,\nincluding its own swapcache removal and mapping lookup.\n\nRefresh the saved mapping after folio_free_swap() so the current folio\nstate is used during migration."}], "id": "CVE-2026-89755", "lastModified": "2026-11-06T18:18:23.547", "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": "2026-09-11T20:20:06.533", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/34a00895d032a414830d41106a09329ae6c251b6"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4fa91f7bbc4135240b67daac03fc17d9e180a331"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8ffedc6573a665cdc31ebe47eae7b32b78d0df83"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/92db780dd644590c751246187e1229d5ac2e5544"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c9c29481d5d4a985a57ece2090a324ba48e362a7"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: Linux kernel: System crash due to stale memory mapping in device migration", "id": "2532241", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2532241"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.1", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["A flaw was found in the Linux kernel's device migration mechanism. When a memory page is freed from the swap cache, a stale mapping of that page might still be used. This incorrect memory accounting can lead to a system crash or instability."], "name": "CVE-2026-89755", "public_date": "2026-09-11T19:46:58Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-89755\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-89755\nhttps://git.kernel.org/stable/c/34a00895d032a414830d41106a09329ae6c251b6\nhttps://git.kernel.org/stable/c/8ffedc6573a665cdc31ebe47eae7b32b78d0df83"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[df263d9a7dffee94ca5391120ee3b0587efa07f1,8ffedc6573a665cdc31ebe47eae7b32b78d0df83)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[df263d9a7dffee94ca5391120ee3b0587efa07f1,34a00895d032a414830d41106a09329ae6c251b6)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.6"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.6)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.4,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.3-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-12T06:00:11.705342+00:00", "updated": "2026-09-15T19:15:16.161942+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}