{"id":"CVE-2026-53288","state":"PUBLISHED","title":"arm64: Reserve an extra page for early kernel mapping","description":"In the Linux kernel, the following vulnerability has been resolved:\n\narm64: Reserve an extra page for early kernel mapping\n\nThe final part of [data, end) segment may overflow into the next page of\ninit_pg_end[1] which is the gap page before early_init_stack[2]:\n\n[1]\ncrash_arm64_v9.0.1> vtop ffffffed00601000\nVIRTUAL           PHYSICAL\nffffffed00601000  83401000\n\nPAGE DIRECTORY: ffffffecffd62000\n   PGD: ffffffecffd62da0 => 10000000833fb003\n   PMD: ffffff80033fb018 => 10000000833fe003\n   PTE: ffffff80033fe008 => 68000083401f03\n  PAGE: 83401000\n\n     PTE        PHYSICAL  FLAGS\n68000083401f03  83401000  (VALID|SHARED|AF|NG|PXN|UXN)\n\n      PAGE       PHYSICAL      MAPPING       INDEX CNT FLAGS\nfffffffec00d0040 83401000                0        0  1 4000 reserved\n\n[2]\nffffffed002c8000 (r) __pi__data\nffffffed0054e000 (d) __pi___bss_start\nffffffed005f5000 (b) __pi_init_pg_dir\nffffffed005fe000 (b) __pi_init_pg_end\nffffffed005ff000 (B) early_init_stack\nffffffed00608000 (b) __pi__end\n\nFor 4K pages, the early kernel mapping may use 2MB block entries but the\nkernel segments are only 64KB aligned. Segment boundaries that fall\nwithin a 2MB block therefore require a PTE table so that different\nattributes can be applied on either side of the boundary.\n\nKERNEL_SEGMENT_COUNT still correctly counts the five permanent kernel\nVMAs registered by declare_kernel_vmas(). However, since commit\n5973a62efa34 (\"arm64: map [_text, _stext) virtual address range\nnon-executable+read-only\"), the early mapper also maps [_text, _stext)\nseparately from [_stext, _etext). This adds one more early-only split\nand can require one more page-table page than the existing\nEARLY_SEGMENT_EXTRA_PAGES allowance reserves.\n\nIncrease the 4K-page early mapping allowance by one page to cover that\nadditional split.\n\n[catalin.marinas@arm.com: rewrote part of the commit log]\n[catalin.marinas@arm.com: expanded the code comment]","publishedAt":"2026-06-26T19:40:48.528Z","updatedAt":"2026-06-26T19:40:48.528Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"fdd380a5950503a07aaaf74536a0c2f223475eb0","status":"affected","lessThan":"a4ff33053da0a34b14abb5c96dc5a48379e26fce","versionType":"git"},{"version":"5973a62efa34c80c9a4e5eac1fca6f6209b902af","status":"affected","lessThan":"dcb89deed40ba55ff7020061712fdabf098cc2cc","versionType":"git"},{"version":"5973a62efa34c80c9a4e5eac1fca6f6209b902af","status":"affected","lessThan":"9fe9e3acaa14921b0cf0d6cc2de5b562499bf721","versionType":"git"},{"version":"5973a62efa34c80c9a4e5eac1fca6f6209b902af","status":"affected","lessThan":"4d8e74ad4585672489da6145b3328d415f50db82","versionType":"git"},{"version":"88025faf2aa08c7468d68d8cb31a53b55aae6ee0","status":"affected","versionType":"git"},{"version":"6.12.54","status":"affected","lessThan":"6.12.91","versionType":"semver"},{"version":"6.17.4","status":"affected","lessThan":"6.18","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/include/asm/kernel-pgtable.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.18","versionType":"semver"},{"version":"6.12.91","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.33","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.10","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/include/asm/kernel-pgtable.h"]}],"references":["https://git.kernel.org/stable/c/a4ff33053da0a34b14abb5c96dc5a48379e26fce","https://git.kernel.org/stable/c/dcb89deed40ba55ff7020061712fdabf098cc2cc","https://git.kernel.org/stable/c/9fe9e3acaa14921b0cf0d6cc2de5b562499bf721","https://git.kernel.org/stable/c/4d8e74ad4585672489da6145b3328d415f50db82"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/53xxx/CVE-2026-53288.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-53288","state":"PUBLISHED","datePublished":"2026-06-26T19:40:48.528Z","dateUpdated":"2026-06-26T19:40:48.528Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-06-09T07:44:35.396Z"},"containers":{"cna":{"title":"arm64: Reserve an extra page for early kernel mapping","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\narm64: Reserve an extra page for early kernel mapping\n\nThe final part of [data, end) segment may overflow into the next page of\ninit_pg_end[1] which is the gap page before early_init_stack[2]:\n\n[1]\ncrash_arm64_v9.0.1> vtop ffffffed00601000\nVIRTUAL           PHYSICAL\nffffffed00601000  83401000\n\nPAGE DIRECTORY: ffffffecffd62000\n   PGD: ffffffecffd62da0 => 10000000833fb003\n   PMD: ffffff80033fb018 => 10000000833fe003\n   PTE: ffffff80033fe008 => 68000083401f03\n  PAGE: 83401000\n\n     PTE        PHYSICAL  FLAGS\n68000083401f03  83401000  (VALID|SHARED|AF|NG|PXN|UXN)\n\n      PAGE       PHYSICAL      MAPPING       INDEX CNT FLAGS\nfffffffec00d0040 83401000                0        0  1 4000 reserved\n\n[2]\nffffffed002c8000 (r) __pi__data\nffffffed0054e000 (d) __pi___bss_start\nffffffed005f5000 (b) __pi_init_pg_dir\nffffffed005fe000 (b) __pi_init_pg_end\nffffffed005ff000 (B) early_init_stack\nffffffed00608000 (b) __pi__end\n\nFor 4K pages, the early kernel mapping may use 2MB block entries but the\nkernel segments are only 64KB aligned. Segment boundaries that fall\nwithin a 2MB block therefore require a PTE table so that different\nattributes can be applied on either side of the boundary.\n\nKERNEL_SEGMENT_COUNT still correctly counts the five permanent kernel\nVMAs registered by declare_kernel_vmas(). However, since commit\n5973a62efa34 (\"arm64: map [_text, _stext) virtual address range\nnon-executable+read-only\"), the early mapper also maps [_text, _stext)\nseparately from [_stext, _etext). This adds one more early-only split\nand can require one more page-table page than the existing\nEARLY_SEGMENT_EXTRA_PAGES allowance reserves.\n\nIncrease the 4K-page early mapping allowance by one page to cover that\nadditional split.\n\n[catalin.marinas@arm.com: rewrote part of the commit log]\n[catalin.marinas@arm.com: expanded the code comment]"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"fdd380a5950503a07aaaf74536a0c2f223475eb0","status":"affected","lessThan":"a4ff33053da0a34b14abb5c96dc5a48379e26fce","versionType":"git"},{"version":"5973a62efa34c80c9a4e5eac1fca6f6209b902af","status":"affected","lessThan":"dcb89deed40ba55ff7020061712fdabf098cc2cc","versionType":"git"},{"version":"5973a62efa34c80c9a4e5eac1fca6f6209b902af","status":"affected","lessThan":"9fe9e3acaa14921b0cf0d6cc2de5b562499bf721","versionType":"git"},{"version":"5973a62efa34c80c9a4e5eac1fca6f6209b902af","status":"affected","lessThan":"4d8e74ad4585672489da6145b3328d415f50db82","versionType":"git"},{"version":"88025faf2aa08c7468d68d8cb31a53b55aae6ee0","status":"affected","versionType":"git"},{"version":"6.12.54","status":"affected","lessThan":"6.12.91","versionType":"semver"},{"version":"6.17.4","status":"affected","lessThan":"6.18","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/include/asm/kernel-pgtable.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.18","versionType":"semver"},{"version":"6.12.91","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.33","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.10","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/include/asm/kernel-pgtable.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/a4ff33053da0a34b14abb5c96dc5a48379e26fce"},{"url":"https://git.kernel.org/stable/c/dcb89deed40ba55ff7020061712fdabf098cc2cc"},{"url":"https://git.kernel.org/stable/c/9fe9e3acaa14921b0cf0d6cc2de5b562499bf721"},{"url":"https://git.kernel.org/stable/c/4d8e74ad4585672489da6145b3328d415f50db82"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-06-26T19:40:48.528Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12.54","versionEndExcluding":"6.12.91"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"6.18.33"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"7.0.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"7.1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17.4"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}