CVE Catalog

CVE-2026-63816

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.13%

3th percentile - higher than 3% of all known CVEs

Summary

Vulnerability in the Linux kernel F2FS filesystem leads to a use-after-free (UAF) of f2fs_inode_info.atomic_inode during garbage collection. Missing reference counting can result in accessing freed memory.

Risk Assessment

Local attack can cause system crash (kernel panic) or potentially arbitrary code execution in kernel context.

Recommendation

Apply the Linux kernel patch that adds a reference count increment on fi->atomic_inode before using its mapping during garbage collection.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS