CVE-2026-43349
MediumIn the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid uninit-value access in f2fs_sanity_check_node_footer syzbot reported a f2fs bug as below: BUG: KMSAN: uninit-value in f2fs_sanity_check_node_footer+0x374/0xa20 fs/f2fs/node.c:1520 f2fs_sanity_check_node_footer+0x374/0xa20 fs/f2fs/node.c:1520 f2fs_finish_read_bio+0xe1e/0x1d60 fs/f2fs/data.c:177 f2fs_read_end_io+0x6ab/0x2220 fs/f2fs/data.c:-1 bio_endio+0x1006/0x1160 block/bio.c:1792 submit_bio_noacct+0x533/0x2960 block/blk-core.c:891 submit_bio+0x57a/0x620 block/blk-core.c:926 blk_crypto_submit_bio include/linux/blk-crypto.h:203 [inline] f2fs_submit_read_bio+0x12c/0x360 fs/f2fs/data.c:557 f2fs_submit_page_bio+0xee2/0x1450 fs/f2fs/data.c:775 read_node_folio+0x384/0x4b0 fs/f2fs/node.c:1481 __get_node_folio+0x5db/0x15d0 fs/f2fs/node.c:1576 f2fs_get_inode_folio+0x40/0x50 fs/f2fs/node.c:1623 do_read_inode fs/f2fs/inode.c:425 [inline] f2fs_iget+0x1209/0x9380 fs/f2fs/inode.c:596 f2fs_fill_super+0x8f5a/0xb2e0 fs/f2fs/super.c:5184 get_tree_bdev_flags+0x6e6/0x920 fs/super.c:1694 get_tree_bdev+0x38/0x50 fs/super.c:1717 f2fs_get_tree+0x35/0x40 fs/f2fs/super.c:5436 vfs_get_tree+0xb3/0x5d0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3763 [inline] do_new_mount+0x885/0x1dd0 fs/namespace.c:3839 path_mount+0x7a2/0x20b0 fs/namespace.c:4159 do_mount fs/namespace.c:4172 [inline] __do_sys_mount fs/namespace.c:4361 [inline] __se_sys_mount+0x704/0x7f0 fs/namespace.c:4338 __x64_sys_mount+0xe4/0x150 fs/namespace.c:4338 x64_sys_call+0x39f0/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The root cause is: in f2fs_finish_read_bio(), we may access uninit data in folio if we failed to read the data from device into folio, let's add a check condition to avoid such issue.
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-908CVE-2026-43349 is classified as CWE-908
See CWE-908 on MITRE CWE for full details on this weakness type.
Affected versions
Linux kernel versions
6.18.13,
6.19.3,
7.0
and later are affected. Fixed in
6.18.25,
7.0.2,
7.1-rc1
and their respective stable series.
References
The following references provide additional information about CVE-2026-43349 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/59970b2586fef4b13e96527b9d232bed30b640cd
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PatchKernel patch commithttps://git.kernel.org/stable/c/7b9161a605e91d0987e2596a245dc1f21621b23f
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PatchKernel patch commithttps://git.kernel.org/stable/c/a10b89343d41ceee1af0ec38d3a74e526c77fa09
Frequently asked questions
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What is CVE-2026-43349?
CVE-2026-43349 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 6.18.13 onward and has been patched in 6.18.25, 7.0.2 and 7.1-rc1. CVE-2026-43349 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-43349?
CVE-2026-43349 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2026-43349?
Yes — CVE-2026-43349 has been patched. Fixed versions include 6.18.25, 7.0.2 and 7.1-rc1. If you are running Linux kernel 6.18.13 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-43349 actively exploited?
No — CVE-2026-43349 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.