{"id":"CVE-2026-43303","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/page_alloc: clear page->private in free_pages_prepare()\n\nSeveral subsystems (slub, shmem, ttm, etc.) use page->private but don't\nclear it before freeing pages","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/page_alloc: clear page->private in free_pages_prepare()\n\nSeveral subsystems (slub, shmem, ttm, etc.) use page->private but don't\nclear it before freeing pages.  When…","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","cwe":["CWE-416"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.18.1, < 6.18.16","linux_kernel >= 6.19, < 6.19.6","linux_kernel = 5.18"],"patched":["linux_kernel 6.19.6"],"published":"2026-05-08","updated":"2026-09-08","sourceUpdated":"2026-09-08T09:18:04.847","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-43303","references":[{"url":"https://git.kernel.org/stable/c/23b82b7a26182ad840ae67d390d7ec9771e8c00f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/3edb8ebbf79b9016040e8f3421d723ae3d542b32","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ac1ea219590c09572ed5992dc233bbf7bb70fef9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d757c793853ec5483eb41ec2942c300b8fa720fb","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e7790ab165713b79b1617ce659742ceb3a859d05","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f9719e32a67b4b00b3c9b133e8b5ffa72a26b67b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.00165,"epssPercentile":0.06131,"ingestedAt":"2026-09-08T13:33:23.990Z","slug":"CVE-2026-43303","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nmm/page_alloc: clear page->private in free_pages_prepare()\n\nSeveral subsystems (slub, shmem, ttm, etc.) use page->private but don't\nclear it before freeing pages.  When these pages are later allocated as\nhigh-order pages and split via split_page(), tail pages retain stale\npage->private values.\n\nThis causes a use-after-free in the swap subsystem.  The swap code uses\npage->private to track swap count continuations, assuming freshly\nallocated pages have page->private == 0.  When stale values are present,\nswap_count_continued() incorrectly assumes the continuation list is valid\nand iterates over uninitialized page->lru containing LIST_POISON values,\ncausing a crash:\n\n  KASAN: maybe wild-memory-access in range [0xdead000000000100-0xdead000000000107]\n  RIP: 0010:__do_sys_swapoff+0x1151/0x1860\n\nFix this by clearing page->private in free_pages_prepare(), ensuring all\nfreed pages have clean state regardless of previous use.\n\n## Affected\n\n- `linux_kernel >= 5.18.1, < 6.18.16`\n- `linux_kernel >= 6.19, < 6.19.6`\n- `linux_kernel = 5.18`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.19.6`","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}