CVEvulnerability
CVE-2026-43303
7.8 HIGH
Official page ↗
- Status
- Modified
- Published
- 2026-05-08
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 7.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-416, CWE-457
Description
In the Linux kernel, the following vulnerability has been resolved:
mm/page_alloc: clear page->private in free_pages_prepare()
Several subsystems (slub, shmem, ttm, etc.) use page->private but don't
clear it before freeing pages. When these pages are later allocated as
high-order pages and split via split_page(), tail pages retain stale
page->private values.
This causes a use-after-free in the swap subsystem. The swap code uses
page->private to track swap count continuations, assuming freshly
allocated pages have page->private == 0. When stale values are present,
swap_count_continued() incorrectly assumes the continuation list is valid
and iterates over uninitialized page->lru containing LIST_POISON values,
causing a crash:
KASAN: maybe wild-memory-access in range [0xdead000000000100-0xdead000000000107]
RIP: 0010:__do_sys_swapoff+0x1151/0x1860
Fix this by clearing page->private in free_pages_prepare(), ensuring all
freed pages have clean state regardless of previous use.
Affected configurations
• linux linux kernel (>= 5.18.1 < 6.18.16)
• linux linux kernel (>= 6.19 < 6.19.6)
• linux linux kernel 5.18
Related
References
- https://git.kernel.org/stable/c/23b82b7a26182ad840ae67d390d7ec9771e8c00f Patch
- https://git.kernel.org/stable/c/3edb8ebbf79b9016040e8f3421d723ae3d542b32 git.kernel.org
- https://git.kernel.org/stable/c/ac1ea219590c09572ed5992dc233bbf7bb70fef9 Patch
- https://git.kernel.org/stable/c/d757c793853ec5483eb41ec2942c300b8fa720fb Patch
- https://git.kernel.org/stable/c/e7790ab165713b79b1617ce659742ceb3a859d05 git.kernel.org
- https://git.kernel.org/stable/c/f9719e32a67b4b00b3c9b133e8b5ffa72a26b67b git.kernel.org
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html cert-portal.siemens.com
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html cert-portal.siemens.com
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html cert-portal.siemens.com