CVE-2025-38163

CVE-2025-38163 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to do sanity check on sbi->total_valid_block_count syzbot reported a f2fs bug as below: ------------[ cut here ]------------ kernel BUG at fs/f2fs/f2fs.h:2521! RIP: 0010:dec_valid_block_count+0x3b2/0x3c0 fs/f2fs/f2fs.h:2521 Call Trace: f2fs_truncate_data_blocks_range+0xc8c/0x11a0 fs/f2fs/file.c:695 truncate_dnode+0x417/0x740 fs/f2fs/node.c:973 truncate_nodes+0x3ec/0xf50 fs/f2fs/node.c:1014 f2fs_truncate_inode_blocks+0x8e3/0x1370 fs/f2fs/node.c:1197 f2fs_do_truncate_blocks+0x840/0x12b0 fs/f2fs/file.c:810 f2fs_truncate_blocks+0x10d/0x300 fs/f2fs/file.c:838 f2fs_truncate+0x417/0x720 fs/f2fs/file.c:888 f2fs_setattr+0xc4f/0x12f0 fs/f2fs/file.c:1112 notify_change+0xbca/0xe90 fs/attr.c:552 do_truncate+0x222/0x310 fs/open.c:65 handle_truncate fs/namei.c:3466 [inline] do_open fs/namei.c:3849 [inline] path_openat+0x2e4f/0x35d0 fs/namei.c:4004 do_filp_open+0x284/0x4e0 fs/namei.c:4031 do_sys_openat2+0x12b/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_creat fs/open.c:1522 [inline] __se_sys_creat fs/open.c:1516 [inline] __x64_sys_creat+0x124/0x170 fs/open.c:1516 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 The reason is: in fuzzed image, sbi->total_valid_block_count is inconsistent w/ mapped blocks indexed by inode, so, we should not trigger panic for such case, instead, let's print log and set fsck flag.

Frequently asked questions

What is CVE-2025-38163?
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to do sanity check on sbi->total_valid_block_count syzbot reported a f2fs bug as below: ------------[ cut here ]------------ kernel BUG at fs/f2fs/f2fs.h:2521! RIP: 0010:dec_valid_block_count+0x3b2/0x3c0 fs/f2fs/f2fs.h:2521 Call Trace: f2fs_truncate_data_blocks_range+0xc8c/0x11a0 fs/f2fs/file.c:695 truncate_dnode+0x417/0x740 fs/f2fs/node.c:973 truncate_nodes+0x3ec/0xf50 fs/f2fs/node.c:1014 f2fs_truncate_inode_blocks+0x8e3/0x1370 fs/f2fs/node.c:1197 f2fs_do_truncate_blocks+0x840/0x12b0 fs/f2fs/file.c:810 f2fs_truncate_blocks+0x10d/0x300 fs/f2fs/file.c:838 f2fs_truncate+0x417/0x720 fs/f2fs/file.c:888 f2fs_setattr+0xc4f/0x12f0 fs/f2fs/file.c:1112 notify_change+0xbca/0xe90 fs/attr.c:552 do_truncate+0x222/0x310 fs/open.c:65 handle_truncate fs/namei.c:3466 [inline] do_open fs/namei.c:3849 [inline] path_openat+0x2e4f/0x35d0 fs/namei.c:4004 do_filp_open+0x284/0x4e0 fs/namei.c:4031 do_sys_openat2+0x12b/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_creat fs/open.c:1522 [inline] __se_sys_creat fs/open.c:1516 [inline] __x64_sys_creat+0x124/0x170 fs/open.c:1516 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 The reason is: in fuzzed image, sbi->total_valid_block_count is inconsistent w/ mapped blocks indexed by inode, so, we should not trigger panic for such case, instead, let's print log and set fsck flag.
How severe is CVE-2025-38163?
CVE-2025-38163 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-38163 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (5th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-38163?
CVE-2025-38163 primarily affects Linux Linux Kernel. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-38163?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-38163 have an EU (EUVD) identifier?
Yes. CVE-2025-38163 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-19781.
When was CVE-2025-38163 published?
CVE-2025-38163 was published on 2025-07-03 and last updated on 2026-06-17.

References

Affected products (2)

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