{"api_version":"1","generated_at":"2026-08-04T05:02:11+00:00","cve":"CVE-2026-64369","urls":{"html":"https://cve.report/CVE-2026-64369","api":"https://cve.report/api/cve/CVE-2026-64369.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64369","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64369"},"summary":{"title":"s390: Revert support for DCACHE_WORD_ACCESS","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390: Revert support for DCACHE_WORD_ACCESS\n\nload_unaligned_zeropad() reads eight bytes from unaligned addresses and may\ncross page boundaries. It handles exceptions which may happen if reading\nfrom the second page results in an exception.\n\nFor pages which are donated to the Ultravisor for secure execution purposes\nthe do_secure_storage_access() exception handler however does not handle\nsuch exceptions correctly. Such an exception may result in an endless\nexception loop which will never be resolved.\n\nAn attempt to fix this [1] turned out to be not sufficient. For now revert\nload_unaligned_zeropad() until this problem has been resolved in a proper\nway.\n\nNote that the implementation of load_unaligned_zeropad() itself is\ncorrect. The revert is just a temporary workaround until there is complete\nfix for secure storage access exceptions.\n\n[1] commit b00be77302d7 (\"s390/mm: Add missing secure storage access fixups for donated memory\")","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-25 10:17:19","updated_at":"2026-07-25 10:17:19"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/c9e0f1517631ac08987f8385817119bccf2f1f12","name":"https://git.kernel.org/stable/c/c9e0f1517631ac08987f8385817119bccf2f1f12","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/c94806905e02cc8e17a69c822d93c41743b7ffc5","name":"https://git.kernel.org/stable/c/c94806905e02cc8e17a69c822d93c41743b7ffc5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/37540b8c287fc817bdbd0c62bb75ad6eab0e5d03","name":"https://git.kernel.org/stable/c/37540b8c287fc817bdbd0c62bb75ad6eab0e5d03","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/be79d285bea70d0edd5015bd487311bfa8cbebc9","name":"https://git.kernel.org/stable/c/be79d285bea70d0edd5015bd487311bfa8cbebc9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64369","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64369","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 802ba53eefc592a6a82231f74e19bafe3256f172 c9e0f1517631ac08987f8385817119bccf2f1f12 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 802ba53eefc592a6a82231f74e19bafe3256f172 be79d285bea70d0edd5015bd487311bfa8cbebc9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 802ba53eefc592a6a82231f74e19bafe3256f172 c94806905e02cc8e17a69c822d93c41743b7ffc5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 802ba53eefc592a6a82231f74e19bafe3256f172 37540b8c287fc817bdbd0c62bb75ad6eab0e5d03 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.7","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.7 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.97 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.39 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.4 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"64369","cve":"CVE-2026-64369","epss":"0.001810000","percentile":"0.079530000","score_date":"2026-07-28","updated_at":"2026-07-29 00:05:33"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["arch/s390/Kconfig","arch/s390/include/asm/asm-extable.h","arch/s390/include/asm/word-at-a-time.h","arch/s390/mm/extable.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"c9e0f1517631ac08987f8385817119bccf2f1f12","status":"affected","version":"802ba53eefc592a6a82231f74e19bafe3256f172","versionType":"git"},{"lessThan":"be79d285bea70d0edd5015bd487311bfa8cbebc9","status":"affected","version":"802ba53eefc592a6a82231f74e19bafe3256f172","versionType":"git"},{"lessThan":"c94806905e02cc8e17a69c822d93c41743b7ffc5","status":"affected","version":"802ba53eefc592a6a82231f74e19bafe3256f172","versionType":"git"},{"lessThan":"37540b8c287fc817bdbd0c62bb75ad6eab0e5d03","status":"affected","version":"802ba53eefc592a6a82231f74e19bafe3256f172","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["arch/s390/Kconfig","arch/s390/include/asm/asm-extable.h","arch/s390/include/asm/word-at-a-time.h","arch/s390/mm/extable.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.7"},{"lessThan":"6.7","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.97","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.39","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.4","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.97","versionStartIncluding":"6.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.39","versionStartIncluding":"6.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.4","versionStartIncluding":"6.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc1","versionStartIncluding":"6.7","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390: Revert support for DCACHE_WORD_ACCESS\n\nload_unaligned_zeropad() reads eight bytes from unaligned addresses and may\ncross page boundaries. It handles exceptions which may happen if reading\nfrom the second page results in an exception.\n\nFor pages which are donated to the Ultravisor for secure execution purposes\nthe do_secure_storage_access() exception handler however does not handle\nsuch exceptions correctly. Such an exception may result in an endless\nexception loop which will never be resolved.\n\nAn attempt to fix this [1] turned out to be not sufficient. For now revert\nload_unaligned_zeropad() until this problem has been resolved in a proper\nway.\n\nNote that the implementation of load_unaligned_zeropad() itself is\ncorrect. The revert is just a temporary workaround until there is complete\nfix for secure storage access exceptions.\n\n[1] commit b00be77302d7 (\"s390/mm: Add missing secure storage access fixups for donated memory\")"}],"providerMetadata":{"dateUpdated":"2026-07-25T08:50:22.543Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/c9e0f1517631ac08987f8385817119bccf2f1f12"},{"url":"https://git.kernel.org/stable/c/be79d285bea70d0edd5015bd487311bfa8cbebc9"},{"url":"https://git.kernel.org/stable/c/c94806905e02cc8e17a69c822d93c41743b7ffc5"},{"url":"https://git.kernel.org/stable/c/37540b8c287fc817bdbd0c62bb75ad6eab0e5d03"}],"title":"s390: Revert support for DCACHE_WORD_ACCESS","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-64369","datePublished":"2026-07-25T08:50:22.543Z","dateReserved":"2026-07-19T15:36:31.783Z","dateUpdated":"2026-07-25T08:50:22.543Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-25 10:17:19","lastModifiedDate":"2026-07-25 10:17:19","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"64369","Ordinal":"1","Title":"s390: Revert support for DCACHE_WORD_ACCESS","CVE":"CVE-2026-64369","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"64369","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390: Revert support for DCACHE_WORD_ACCESS\n\nload_unaligned_zeropad() reads eight bytes from unaligned addresses and may\ncross page boundaries. It handles exceptions which may happen if reading\nfrom the second page results in an exception.\n\nFor pages which are donated to the Ultravisor for secure execution purposes\nthe do_secure_storage_access() exception handler however does not handle\nsuch exceptions correctly. Such an exception may result in an endless\nexception loop which will never be resolved.\n\nAn attempt to fix this [1] turned out to be not sufficient. For now revert\nload_unaligned_zeropad() until this problem has been resolved in a proper\nway.\n\nNote that the implementation of load_unaligned_zeropad() itself is\ncorrect. The revert is just a temporary workaround until there is complete\nfix for secure storage access exceptions.\n\n[1] commit b00be77302d7 (\"s390/mm: Add missing secure storage access fixups for donated memory\")","Type":"Description","Title":"s390: Revert support for DCACHE_WORD_ACCESS"}]}}}