CVSS 7.8 · High EPSS 0,19%
Kerentanan Double Free pada linux kernel. Skor CVSS 3.1 7.8 (High) menurut NVD.
In the Linux kernel, the following vulnerability has been resolved: xen/privcmd: fix double free via VMA splitting privcmd_vm_ops defines .close (privcmd_close), but neither .may_split nor .open. When userspace does a partial munmap() on a privcmd mapping, the kernel splits the VMA via __split_vma(). Since may_split is NULL, the split is allowed. vm_area_dup() copies vm_private_data (a pages array allocated in alloc_empty_pages()) into the new VMA without any fixup, because there is no .open callback. Both VMAs now point to the same pages array. When the unmapped portion is closed, privcmd_close() calls: - xen_unmap_domain_gfn_range() - xen_free_unpopulated_pages() - kvfree(pages) The surviving VMA still holds the dangling pointer. When it is later destroyed, the same sequence runs again, which leads to a double free. Fix this issue by adding a .may_split callback denying the VMA split. This is XSA-487 / CVE-2026-31787
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
· uraikan di kalkulator | Vendor | Produk | Versi terdampak |
|---|---|---|
| linux | linux kernel | Versi 3.8 hingga sebelum 5.10.254 |
| linux | linux kernel | Versi 5.11 hingga sebelum 5.15.204 |
| linux | linux kernel | Versi 5.16 hingga sebelum 6.1.170 |
| linux | linux kernel | Versi 6.2 hingga sebelum 6.6.137 |
| linux | linux kernel | Versi 6.7 hingga sebelum 6.12.85 |
| linux | linux kernel | Versi 6.13 hingga sebelum 6.18.26 |
| linux | linux kernel | Versi 6.19 hingga sebelum 7.0.3 |
| linux | linux kernel | Versi 7.1 rc1 |
| linux | linux kernel | Versi 7.1 rc2 |