{"id":"CVE-2026-72172","title":"mm/mm_init: fix uninitialized struct pages for ZONE_DEVICE","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/mm_init: fix uninitialized struct pages for ZONE_DEVICE\n\nIf DAX memory is hotplugged into an unoccupied subsection of an early\nsection, section_activate() reuses the…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < c5ef574d57e4a701485c13f26822328c91f05413","Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < 511a60e71aec308b24722cffc1912bf6befb87bf","Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < 11f2826e9ee6f24aaa774e3dcd75abbe4b3091b6","Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < da5234df0941665f3a3f5b80f3dab94046537be0","Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < b91e27bce37cab9f35de0059278ebe457ca9878b","Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < cd681403a87085562499d60325b7b45d3be11217","Linux 5.19"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T18:43:19.574652Z"},"published":"2026-08-15","updated":"2026-10-16","sourceUpdated":"2026-10-16T18:45:00.307Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-72172","references":[{"url":"https://git.kernel.org/stable/c/c5ef574d57e4a701485c13f26822328c91f05413"},{"url":"https://git.kernel.org/stable/c/511a60e71aec308b24722cffc1912bf6befb87bf"},{"url":"https://git.kernel.org/stable/c/11f2826e9ee6f24aaa774e3dcd75abbe4b3091b6"},{"url":"https://git.kernel.org/stable/c/da5234df0941665f3a3f5b80f3dab94046537be0"},{"url":"https://git.kernel.org/stable/c/b91e27bce37cab9f35de0059278ebe457ca9878b"},{"url":"https://git.kernel.org/stable/c/cd681403a87085562499d60325b7b45d3be11217"}],"tags":["cve.org"],"epss":0.00169,"epssPercentile":0.05787,"ingestedAt":"2026-10-16T19:46:24.424Z","slug":"CVE-2026-72172","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nmm/mm_init: fix uninitialized struct pages for ZONE_DEVICE\n\nIf DAX memory is hotplugged into an unoccupied subsection of an early\nsection, section_activate() reuses the unoptimized boot memmap.  However,\ncompound_nr_pages() still assumes that vmemmap optimization is in effect\nand initializes only the reduced number of struct pages.  As a result, the\nremaining tail struct pages are left uninitialized, which can later lead\nto unexpected behavior or crashes.\n\nFix this by treating early sections as unoptimized when calculating how\nmany struct pages to initialize.\n\n## Affected\n\n- `Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < c5ef574d57e4a701485c13f26822328c91f05413`\n- `Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < 511a60e71aec308b24722cffc1912bf6befb87bf`\n- `Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < 11f2826e9ee6f24aaa774e3dcd75abbe4b3091b6`\n- `Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < da5234df0941665f3a3f5b80f3dab94046537be0`\n- `Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < b91e27bce37cab9f35de0059278ebe457ca9878b`\n- `Linux >= 6fd3620b342861de9547ea01d28f664892ef51a1 < cd681403a87085562499d60325b7b45d3be11217`\n- `Linux 5.19`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}