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NVD / CVE Program· CNA Linux

CVE-2025-38218: f2fs: fix to do sanity check on sit_bitmap_size

Noroxi assessment

Priority: Monitor (action score 22/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.19% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 38ef48a8afef8df646b6f6ae7abb872f18b533c1, 3e5ac62a56a24f4d88ce8ffd7bc452428b235868, 5db0d252c64e91ba1929c70112352e85dc5751e7; azl3 kernel 6.6.92.2-2 on Azure Linux 3.0 6.6.96.1-1.
  • Severity is disputed: the assigning authority (CNA) scores it 7.8, NVD 5.5.

Low priority for now. Upgrade to Linux Linux 38ef48a8afef8df646b6f6ae7abb872f18b533c1, 3e5ac62a56a24f4d88ce8ffd7bc452428b235868, 5db0d252c64e91ba1929c70112352e85dc5751e7; azl3 kernel 6.6.92.2-2 on Azure Linux 3.0 6.6.96.1-1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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.

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
Jul 4, 2025
Updated
Aug 5, 2026
EPSS
0.1% · 8th percentile
CWE
—

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CNA vs NVD score

NVD
5.5
CNA · Linux
7.8
2.3 point gap

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel
debiandebian linux

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • debian debian linux11.0
  • linux linux kernel5.11 and later · before 5.15.186
  • linux linux kernel5.16 and later · before 6.1.142
  • linux linux kernel3.8 and later · before 5.10.239
  • linux linux kernel6.7 and later · before 6.12.35
  • linux linux kernel6.13 and later · before 6.15.4
  • linux linux kernel6.2 and later · before 6.6.95

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 3.8affected
    • 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 and later · before 82f51bff393e4c12cf4de553120ca831cfa4ef19affected · git
    • 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 and later · before 38ef48a8afef8df646b6f6ae7abb872f18b533c1affected · git
    • 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 and later · before ad862f71016ba38039df1c96ed55c0a4314cc183affected · git
    • 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 and later · before 79ef8a6c4ec53d327580fd7d2b522cf4f1d05b0caffected · git
    • 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 and later · before ee1b421c469876544e297ec1090574bd76100247affected · git
    • 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 and later · before 3e5ac62a56a24f4d88ce8ffd7bc452428b235868affected · git
    • 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 and later · before 5db0d252c64e91ba1929c70112352e85dc5751e7affected · git
    • before 3.8not affected · semver
    • 5.10.239 and later · up to and including 5.10.*not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.147-16.1.147-1
Debian:13linuxbefore 6.12.35-16.12.35-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe…KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2025-38211Jul 4, 2025 · RDMA/iwcm: Fix use-after-free of work objects after cm_id destruction
    31Monitor
  • ← EarlierCVE-2025-38217Jul 4, 2025 · hwmon: (ftsteutates) Fix TOCTOU race in fts_read()
    18Monitor
  • Later →CVE-2025-38219Jul 4, 2025 · f2fs: prevent kernel warning due to negative i_nlink from corrupted image
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux38ef48a8afef8df646b6f6ae7abb872f18b533c1Vendor (CNA)
Linux Linux3e5ac62a56a24f4d88ce8ffd7bc452428b235868Vendor (CNA)
Linux Linux5db0d252c64e91ba1929c70112352e85dc5751e7Vendor (CNA)
Linux Linux79ef8a6c4ec53d327580fd7d2b522cf4f1d05b0cVendor (CNA)
Linux Linux82f51bff393e4c12cf4de553120ca831cfa4ef19Vendor (CNA)
Linux Linuxad862f71016ba38039df1c96ed55c0a4314cc183Vendor (CNA)
Linux Linuxee1b421c469876544e297ec1090574bd76100247Vendor (CNA)
azl3 kernel 6.6.92.2-2 on Azure Linux 3.06.6.96.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:linux6.1.147-1 · Debian:12Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

—

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (8 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records