{"id":"CVE-2026-63875","revision":null,"records":[{"revision":"6b438e26462f43a991cf9a93bb59579b","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-63875","aliases":[],"title":"arm64: tlb: Flush walk cache when unsharing PMD tables","description":"In the Linux kernel, the following vulnerability has been resolved:\n\narm64: tlb: Flush walk cache when unsharing PMD tables\n\nWhen huge_pmd_unshare() is called to unshare a PMD table, the\ntlb_unshare_pmd_ptdesc() function sets tlb->unshared_tables=true\nbut the aarch64 tlb_flush() only checked tlb->freed_tables to\ndetermine whether to use TLBF_NONE (vae1is, invalidates walk\ncache) or TLBF_NOWALKCACHE (vale1is, leaf-only).\n\nThis caused the stale PMD page table entry to remain in the walk cache\nafter unshare, potentially leading to incorrect page table walks.\n\nFix by including unshared_tables in the check, so that when\nunsharing tables, TLBF_NONE is used and the walk cache is properly\ninvalidated.\n\nHere is the detailed distinction between vae1is and vale1is:\n\n| Instruction Combination | Actual Invalidation Scope |\n| ------------------------ | --------------------------------------------------|\n| `VAE1IS` + TTL=`0` | All entries at all levels (full invalidation) |\n| `VAE1IS` + TTL=`2` (L2) | Non-leaf at Level 0/1 + leaf at Level 2 |\n| `VALE1IS` + TTL=`0` | Leaf entries at all levels (non-leaf not cleared) |\n| `VALE1IS` + TTL=`2` (L2) | Leaf entry at Level 2 only |","state":0,"publishedAt":"2026-07-19T14:54:48.842+00:00","modifiedAt":"2026-10-19T20:17:53.723+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/arm64/include/asm/tlb.h\"\n ],\n \"versions\": [\n {\n \"version\": \"6495204f8219a57859669d618b25d06176d5a872\",\n \"lessThan\": \"dced308d7d6a0de1c09d2058f38f1aaaf5cbb914\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"ce4cf24761467756462c0e1dbe4a5e9c9eb520fc\",\n \"lessThan\": \"47490bbb05c8c0e09cc3cfd237d8934ffc340583\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"daa6707b71a2da23a82979fa21f788aeb706f1a2\",\n \"lessThan\": \"0199c9d57861f17b556b6cba1f765c7cce79745b\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"ff37dd18ce7739a26aab0cc2d31006a45e6bde63\",\n \"lessThan\": \"d766a49d9b55705c4737cd8bb5d3faa2d31330fd\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"da06bb0ca45b1ca6f1ab55023e34e61a520337f3\",\n \"lessThan\": \"8ca7284da0e67b3e71d90ec17f08286774245ad9\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"9b671f6f432be07c0ddd66e437d6d0e0db684f83\",\n \"lessThan\": \"fe93e907b1af03cc229a80aa64a570a103d2b279\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"8ce720d5bd91e9dc16db3604aa4b1bf76770a9a1\",\n \"lessThan\": \"48125cd9c55cbe297b59fd1f9bda48b0960bd181\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"8ce720d5bd91e9dc16db3604aa4b1bf76770a9a1\",\n \"lessThan\": \"c2ff4764e03e7a8d758352f4aceb8fe1be6ac971\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"5.10.253\",\n \"lessThan\": \"5.10.259\",\n \"status\": \"affected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.15.203\",\n \"lessThan\": \"5.15.210\",\n \"status\": \"affected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.1.167\",\n \"lessThan\": \"6.1.176\",\n \"status\": \"affected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.6.127\",\n \"lessThan\": \"6.6.143\",\n \"status\": \"affected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.12.74\",\n \"lessThan\": \"6.12.93\",\n \"status\": \"affected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.18.13\",\n \"lessThan\": \"6.18.35\",\n \"status\": \"affected\",\n \"versionType\": \"semver\"\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/arm64/include/asm/tlb.h\"\n ],\n \"versions\": [\n {\n \"version\": \"6.19\",\n \"status\": \"affected\"\n },\n {\n \"version\": \"0\",\n \"lessThan\": \"6.19\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.10.259\",\n \"lessThanOrEqual\": \"5.10.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.15.210\",\n \"lessThanOrEqual\": \"5.15.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.1.176\",\n \"lessThanOrEqual\": \"6.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.6.143\",\n \"lessThanOrEqual\": \"6.6.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.12.93\",\n \"lessThanOrEqual\": \"6.12.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.18.35\",\n \"lessThanOrEqual\": \"6.18.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.0.12\",\n \"lessThanOrEqual\": \"7.0.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.1\",\n \"lessThanOrEqual\": \"*\",\n \"status\": \"unaffected\",\n \"versionType\": \"original_commit_for_fix\"\n }\n ]\n }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/dced308d7d6a0de1c09d2058f38f1aaaf5cbb914","https://git.kernel.org/stable/c/47490bbb05c8c0e09cc3cfd237d8934ffc340583","https://git.kernel.org/stable/c/0199c9d57861f17b556b6cba1f765c7cce79745b","https://git.kernel.org/stable/c/d766a49d9b55705c4737cd8bb5d3faa2d31330fd","https://git.kernel.org/stable/c/8ca7284da0e67b3e71d90ec17f08286774245ad9","https://git.kernel.org/stable/c/fe93e907b1af03cc229a80aa64a570a103d2b279","https://git.kernel.org/stable/c/48125cd9c55cbe297b59fd1f9bda48b0960bd181","https://git.kernel.org/stable/c/c2ff4764e03e7a8d758352f4aceb8fe1be6ac971"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-63875","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-63875","identifiers":["CVE-2026-63875"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-08T19:47:20.1649891+00:00","complete":true,"records":1769,"lastAttemptAt":"2026-11-08T19:47:20.1649891+00:00","lastSuccessAt":"2026-11-08T19:47:20.3943637+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:20.3943658+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-eaa64dac63caa79c8d4905619258c41c51b39e461b996124e1a21b5e85e7e738-5ed072895efd00dfc9298eaa4ea0dc8e51b29da4254bc61a9f28835ec1fa6ea6","complete":true,"records":421260,"lastAttemptAt":"2026-11-08T19:47:19.7023073+00:00","lastSuccessAt":"2026-11-08T19:47:19.6080199+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:19.7023073+00:00","snapshotPublishedAt":"2026-11-08T19:27:43+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. 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-f1b70ba09149408c9b3f93f80725b8b9","complete":true,"records":13654,"lastAttemptAt":"2026-11-08T19:48:04.0257169+00:00","lastSuccessAt":"2026-11-08T19:48:04.022+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:48:04.022+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13706,"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":"2026-11-08T19:47:20.1649891+00:00","complete":true,"records":1096,"lastAttemptAt":"2026-11-08T19:47:20.1649891+00:00","lastSuccessAt":"2026-11-08T19:47:20.3951142+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:20.3951146+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-3b79c659b4ac42b2801e63ff6ff3a882","complete":false,"records":13666,"lastAttemptAt":"2026-11-08T19:47:46.1695591+00:00","lastSuccessAt":"2026-11-08T19:47:46.166+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:46.166+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13206,"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":"2026-11-08T19:47:20.0165357+00:00","lastSuccessAt":"2026-11-08T11:07:07.068788+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:20.0165357+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":"2026-11-08T19:47:19.7560084+00:00","lastSuccessAt":"2026-11-06T19:03:17.0399903+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:19.7560084+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-964c14035e6f0f6478b2870fad6a7ef9f6045876d4a12af2c2e514521e54b6af","complete":true,"records":3055,"lastAttemptAt":"2026-11-08T19:47:20.1181272+00:00","lastSuccessAt":"2026-11-08T11:07:12.1927025+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:20.1181272+00:00","snapshotPublishedAt":"2026-11-08T11:02:46+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":"2026-11-08T19:47:19.9161497+00:00","lastSuccessAt":"2026-11-08T11:06:56.2918717+00:00","error":null,"lastVerifiedAt":"2026-11-08T19:47:19.9161497+00:00","snapshotPublishedAt":"2026-11-08T11:02:50+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}