CVE intelligence

CVE-2026-63816

Vulnerability intelligence

Published Jul 19, 2026Sources checked Oct 21, 2026

7.8HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-63816 and is rated High severity with a CVSS score of 7.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

CISA KEVNot listedBased on the latest collected catalog

EPSS0.1%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is 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.

Source: NVD