CVE Intelligence
Medium Memory corruption

CVE-2026-43349 — f2fs: fix to avoid uninit-value access in f2fs_sanity_check_node_footer

In 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.

Published May 8, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.2% (30-day exploitation probability)+1
  • Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.16%
ahead of 5% of scored CVEs · Oct 14, 2026
Affects
Linux
Linux and 1 more
CVSS base
5.5
Medium · 1 source(s)

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Documented patch — git.kernel.org (NIST National Vulnerability Database)
  • Documented patch — git.kernel.org (NIST National Vulnerability Database)
  • Documented patch — git.kernel.org (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Linux Linux, Linux Linux Kernel).
  2. Apply the fixed version or the patch documented under Remediation.
  3. Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Linux Linux ≥ 855c54f1803e3ebc613677b4f389c7f92656a1fc and < 59970b2586fef4b13e96527b9d232bed30b640cd≥ 50ac3ecd8e05b6bcc350c71a4307d40c030ec7e4 and < a10b89343d41ceee1af0ec38d3a74e526c77fa09≥ 50ac3ecd8e05b6bcc350c71a4307d40c030ec7e4 and < 7b9161a605e91d0987e2596a245dc1f21621b23fversion c386753db52b3a80afa6612bfdcb925aa5ca260f≥ 6.18.13 and < 6.18.25≥ 6.19.3 and < 6.20version 7.0 Vulnerable CVE Program (cve.org) e CISA ADP
Linux Linux Kernel ≥ 6.18.13 and < 6.18.25≥ 6.19.3 and < 7.0≥ 7.0.1 and < 7.0.2 Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
5.5 CVSS 3.1 Medium 1.8 3.6 nvd@nist.gov via NIST National Vulnerability Database
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-908 · Use of Uninitialized Resource

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.16%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
  • Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
endpoint telemetry (EDR)crash dumps

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · linux/linux
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Fix documented
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 5.5
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    May 8, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

3 on the record

Elsewhere on this site

Linux
every CVE for this vendor
Memory corruption
same class
CWE-908
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-99999 ipv4: validate checksum_start before completing checksum 7h
  • CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 7h
  • CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 1d
  • CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
  • CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
  • CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No CISA SSVC assessment.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-43349 is "f2fs: fix to avoid uninit-value access in f2fs_sanity_check_node_footer", rated Medium. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.16% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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