Vulnerability in Linux
CVE-2026-63816
In the Linux kernel, the following vulnerability has been resolved: f2fs: atomic: fix UAF issue on f2fs_inode_info.atomic_inode - ioctl(F2FS_IOC_GARBAGE_COLLECT_RANGE) - shrink - f2fs_gc - gc_data_segment - ra_data_block(cow_inode) - mapping = F2FS_I(inode)->atomic_inode->i_mapping : f2fs_is_cow_file(cow_inode) is true - f2fs_evict_inode(atomic_inode) - clear_inode_flag(fi->cow_inode, FI_COW_FILE) - F2FS_I(fi->cow_inode)->atomic_inode = NULL ... - truncate_inode_pages_final(atomic_inode) - f2fs_grab_cache_folio(mapping) : create folio in atomic_inode->mapping - clear_inode(atomic_inode) - BUG_ON(atomic_inode->i_data.nrpages) We need to add a reference on fi->atomic_inode before using its mapping field during garbage collection, otherwise, it will cause UAF issue.
EPSS: 0.001 (2.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux — versions 5.19, 7.2-rc1, 6.6.145
References
Frequently asked questions
- What is CVE-2026-63816?
- CVE-2026-63816 is a high-severity vulnerability in Linux. CVSS score: 7.8/10. Published 2026-07-19.
- How severe is CVE-2026-63816?
- High severity. CVSS v3 base score is 7.8 out of 10.