CVE-2025-38218

MEDIUM EPSS 4.2%
Published Jul 4, 202512mo ago · Modified Jun 17, 20261w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Jul 4, 2025 12mo ago
Last Modified Jun 17, 2026 1w ago

Description

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to do sanity check on sit_bitmap_size w/ below testcase, resize will generate a corrupted image which contains inconsistent metadata, so when mounting such image, it will trigger kernel panic: touch img truncate -s $((512*1024*1024*1024)) img mkfs.f2fs -f img $((256*1024*1024)) resize.f2fs -s -i img -t $((1024*1024*1024)) mount img /mnt/f2fs ------------[ cut here ]------------ kernel BUG at fs/f2fs/segment.h:863! Oops: invalid opcode: 0000 [#1] SMP PTI CPU: 11 UID: 0 PID: 3922 Comm: mount Not tainted 6.15.0-rc1+ #191 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:f2fs_ra_meta_pages+0x47c/0x490 Call Trace: f2fs_build_segment_manager+0x11c3/0x2600 f2fs_fill_super+0xe97/0x2840 mount_bdev+0xf4/0x140 legacy_get_tree+0x2b/0x50 vfs_get_tree+0x29/0xd0 path_mount+0x487/0xaf0 __x64_sys_mount+0x116/0x150 do_syscall_64+0x82/0x190 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fdbfde1bcfe The reaseon is: sit_i->bitmap_size is 192, so size of sit bitmap is 192*8=1536, at maximum there are 1536 sit blocks, however MAIN_SEGS is 261893, so that sit_blk_cnt is 4762, build_sit_entries() -> current_sit_addr() tries to access out-of-boundary in sit_bitmap at offset from [1536, 4762), once sit_bitmap and sit_bitmap_mirror is not the same, it will trigger f2fs_bug_on(). Let's add sanity check in f2fs_sanity_check_ckpt() to avoid panic.

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
4.2% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Affected Products 7

VendorProductVersionRange
linuxlinux_kernel*≥3.8  –  <5.10.239
linuxlinux_kernel*≥5.11  –  <5.15.186
linuxlinux_kernel*≥5.16  –  <6.1.142
linuxlinux_kernel*≥6.2  –  <6.6.95
linuxlinux_kernel*≥6.7  –  <6.12.35
linuxlinux_kernel*≥6.13  –  <6.15.4
debiandebian_linux11.0any

References 9

  • git.kernel.org https://git.kernel.org/stable/c/38ef48a8afef8df646b6f6ae7abb872f18b533c1
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/3e5ac62a56a24f4d88ce8ffd7bc452428b235868
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5db0d252c64e91ba1929c70112352e85dc5751e7
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/79ef8a6c4ec53d327580fd7d2b522cf4f1d05b0c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/82f51bff393e4c12cf4de553120ca831cfa4ef19
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ad862f71016ba38039df1c96ed55c0a4314cc183
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ee1b421c469876544e297ec1090574bd76100247
    Patch
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
    Mailing ListThird Party Advisory
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
    Mailing ListThird Party Advisory

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/38ef48a8afef8df646b6f6ae7abb872f18b533c1
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/3e5ac62a56a24f4d88ce8ffd7bc452428b235868
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5db0d252c64e91ba1929c70112352e85dc5751e7
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/79ef8a6c4ec53d327580fd7d2b522cf4f1d05b0c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/82f51bff393e4c12cf4de553120ca831cfa4ef19
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ad862f71016ba38039df1c96ed55c0a4314cc183
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ee1b421c469876544e297ec1090574bd76100247
    Patch