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.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/56038756aae68312df00d4aa1d97e51ef3aca725
https://git.kernel.org/stable/c/7d3ae21783e5914c1761ac7d63f882d3d70800e9
https://git.kernel.org/stable/c/a499f77c06050a28c897bdbd86cd2f0721ae0743
https://git.kernel.org/stable/c/a805fec35c201c59643ddcde713bce4051c8ee27
https://git.kernel.org/stable/c/e0288584baa5dc41df4a829a023c4c1b33fe53d7

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-19 12:16

Updated : 2026-08-17 05:17

NVD link : CVE-2026-63816

Mitre link : CVE-2026-63816

CVE.ORG link : CVE-2026-63816

JSON object : View

Products Affected

No product.

CWE

No CWE.

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