{"id":"CVE-2026-97943","revision":null,"records":[{"revision":"bfd83e56260b4bba93f54f304b59113b","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-97943","aliases":[],"title":"x86/mm/pat: Acquire init_mm write lock on collapse to avoid UAF","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/mm/pat: Acquire init_mm write lock on collapse to avoid UAF\n\nx86 implements page attribute modification using its Change Page\nAttributes (CPA) mechanism.\n\nThis tracks properties of ranges such as cache mode through x86 page\nattributes, and as part of that logic manipulates kernel page tables.\n\nSince commit:\n\n  41d88484c71c (\"x86/mm/pat: restore large ROX pages after fragmentation\")\n\nranges of kernel page table entries can be collapsed into\nhuge page table entries as part of this logic.\n\nAs part of this collapse, it frees the page tables which the collapsed\nentries previously pointed to, and it does so without any relevant locks\nbeing held to preclude concurrent kernel page table walkers.\n\nThe only way this code can be reached is if CPA_COLLAPSE is specified, and\nthis is only set in set_memory_rox() via:\n\nset_memory_rox()\n-> change_page_attr_set_clr()\n-> cpa_flush()\n-> cpa_collapse_large_pages()\n\nNotable users of this are execmem and BPF when manipulating executable\nmappings.\n\nHowever, this is problematic for ptdump as it walks ranges it does not own\nand thus runs the risk of a use-after-free on page tables freed underneath\nit.\n\nIn addition, concurrent CPA collapse operations are possible which can also\ncause races.\n\nResolve the issue by acquiring the mmap write lock on init_mm across the\nwhole operation.\n\nIt is safe to acquire a sleeping lock as all the callers invoke\nset_memory_rox() from process context and in any case,\nchange_page_attr_set_clr() calls vm_unmap_alias() which ultimately takes a\nmutex, disallowing atomic context here.","state":0,"publishedAt":"2026-09-25T10:22:54.787+00:00","modifiedAt":"2026-10-19T09:11:09.731+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"arch/x86/mm/pat/set_memory.c\",\n                        \"include/linux/mmap_lock.h\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"41d88484c71cd4f659348da41b7b5b3dbd3be1f6\",\n                            \"lessThan\": \"35820cf8dd521f5a651e221483015b0586794516\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"41d88484c71cd4f659348da41b7b5b3dbd3be1f6\",\n                            \"lessThan\": \"93b98882198b15bd482da1fe8e84b05c7c3b3d83\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"41d88484c71cd4f659348da41b7b5b3dbd3be1f6\",\n                            \"lessThan\": \"a1c7570cedd03372812a5b693732880867babbca\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"arch/x86/mm/pat/set_memory.c\",\n                        \"include/linux/mmap_lock.h\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.15\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.15\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.53\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.7\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/35820cf8dd521f5a651e221483015b0586794516","https://git.kernel.org/stable/c/93b98882198b15bd482da1fe8e84b05c7c3b3d83","https://git.kernel.org/stable/c/a1c7570cedd03372812a5b693732880867babbca"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-97943","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-97943","identifiers":["CVE-2026-97943"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. 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Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-ad1daa57fd0d4d4ba18256a2340415a0","complete":false,"records":13654,"lastAttemptAt":"2026-11-09T01:13:59.0733242+00:00","lastSuccessAt":"2026-11-09T01:13:59.069+00:00","error":null,"lastVerifiedAt":"2026-11-09T01:13:59.069+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13626,"expectedIdentifiers":13706,"failedIdentifiers":0},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-11-09T01:02:10.7447709+00:00","complete":true,"records":1096,"lastAttemptAt":"2026-11-09T01:02:10.7447709+00:00","lastSuccessAt":"2026-11-09T01:02:10.8958676+00:00","error":null,"lastVerifiedAt":"2026-11-09T01:02:10.8958678+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-cfd5ade15e524f2aab9bbdd1588fc1b0","complete":true,"records":13666,"lastAttemptAt":"2026-11-09T01:02:13.0307833+00:00","lastSuccessAt":"2026-11-09T01:02:13.027+00:00","error":null,"lastVerifiedAt":"2026-11-09T01:02:13.027+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13706,"expectedIdentifiers":13706,"failedIdentifiers":0},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-980593e6977a6d1b4fb1eed5a1ffe88a468736f89f0a06f710924ad59132c023","complete":true,"records":9914,"lastAttemptAt":"2026-11-09T01:02:10.6696355+00:00","lastSuccessAt":"2026-11-08T11:07:07.068788+00:00","error":null,"lastVerifiedAt":"2026-11-09T01:02:10.6696355+00:00","snapshotPublishedAt":"2026-11-08T11:02:46+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-fde804134ecdda0ddd5ff5c26ee1fff5a6fa659311f7ef2e51c6ad54964db0e2","complete":true,"records":1971,"lastAttemptAt":"2026-11-09T01:02:10.4684348+00:00","lastSuccessAt":"2026-11-06T19:03:17.0399903+00:00","error":null,"lastVerifiedAt":"2026-11-09T01:02:10.4684348+00:00","snapshotPublishedAt":"2026-11-06T18:17:57+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-3b1150af6d7ada2c07356cbab4ead5224c1485027890f71c71d0742cddf0b9e8","complete":true,"records":3055,"lastAttemptAt":"2026-11-09T01:02:10.6816953+00:00","lastSuccessAt":"2026-11-09T00:02:23.4330288+00:00","error":null,"lastVerifiedAt":"2026-11-09T01:02:10.6816953+00:00","snapshotPublishedAt":"2026-11-08T23:17:54+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-f8647d7ba64b1ba0dfdc7130944766d5b36d5b77d18fff0c79e651a4cff3c2b9","complete":true,"records":231293,"lastAttemptAt":"2026-11-09T01:02:10.5692363+00:00","lastSuccessAt":"2026-11-08T11:06:56.2918717+00:00","error":null,"lastVerifiedAt":"2026-11-09T01:02:10.5692363+00:00","snapshotPublishedAt":"2026-11-08T11:02:50+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}