CVE-2023-53829: 
Linux Kernel vulnerability analysis and mitigation

CVE-2023-53829 is a kernel bug in the Linux kernel's F2FS (Flash-Friendly File System) subsystem, specifically related to improper inode handling when an atomic write operation is aborted. The vulnerability causes a kernel BUG (f2fs_bug_on) during inode eviction when a dirty inode flag (FI_DIRTY_INODE) remains set after aborting an atomic file operation, leading to a kernel panic. It was published on December 9, 2025, and affects the Linux kernel. The CVSS category is estimated as HIGH with an EPSS score of 0.000170 (Feedly).

The root cause is a missing inode flush in f2fs_abort_atomic_write(): when an atomic write is aborted, the inode is marked dirty via f2fs_mark_inode_dirty_sync(), but is not subsequently flushed before eviction. This leaves the FI_DIRTY_INODE flag set, which triggers a f2fs_bug_on() assertion failure in f2fs_evict_inode() at fs/f2fs/inode.c:869. The call stack proceeds through f2fs_abort_atomic_write → f2fs_evict_inode → evict → evict_inodes → generic_shutdown_super, typically triggered during filesystem unmount or process exit. This is classified as an improper state management issue (CWE-664) and was originally identified via a syzbot fuzzer report on kernel version 6.4.0-syzkaller (Feedly).

Successful triggering of this vulnerability causes a kernel BUG (invalid opcode / kernel panic) on systems using the F2FS filesystem, resulting in a denial of service (system crash). The impact is limited to availability — there is no evidence of confidentiality or integrity compromise. Systems using F2FS-formatted storage (common on Android devices and embedded Linux systems) are at risk of unexpected reboots or data loss due to unclean shutdowns (Feedly).

There is no known public exploit code or evidence of in-the-wild exploitation for CVE-2023-53829. The EPSS score is very low at 0.000170, indicating minimal probability of exploitation in the near term. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog. Exploitation requires local access to a system with an F2FS-mounted filesystem and the ability to trigger an aborted atomic write operation, limiting the practical attack surface (Feedly).

The fix involves flushing the inode in f2fs_abort_atomic_write() before eviction to clear the FI_DIRTY_INODE flag, preventing the f2fs_bug_on() assertion from triggering. Patches have been committed to the stable Linux kernel tree (commits 1c64dbe8fa35, a3ab55746612, bfa7853bb47f). Users should update to a patched Linux kernel version that includes these fixes. As a workaround, avoiding the use of F2FS atomic write operations or migrating to a different filesystem (e.g., ext4) on affected systems can reduce exposure (Feedly, Kernel Git).