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NVD / CVE Program· CNA Linux

CVE-2026-23235: f2fs: fix out-of-bounds access in sysfs attribute read/write

Noroxi assessment

Priority: Monitor (action score 28/100)

  • 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: 0.17% (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 3a905e183c047577b154f08a78ac3039e9454703, 438a405fbad6882df0e34b3e1a16839a71f04240, 4ef30b9f1641c9e877792df6b049f1cf507d002d.

Low priority for now. Upgrade to Linux Linux 3a905e183c047577b154f08a78ac3039e9454703, 438a405fbad6882df0e34b3e1a16839a71f04240, 4ef30b9f1641c9e877792df6b049f1cf507d002d 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 out-of-bounds access in sysfs attribute read/write Some f2fs sysfs attributes suffer from out-of-bounds memory access and incorrect handling of integer values whose size is not 4 bytes. For example: vm:~# echo 65537 > /sys/fs/f2fs/vde/carve_out vm:~# cat /sys/fs/f2fs/vde/carve_out 65537 vm:~# echo 4294967297 > /sys/fs/f2fs/vde/atgc_age_threshold vm:~# cat /sys/fs/f2fs/vde/atgc_age_threshold 1 carve_out maps to {struct f2fs_sb_info}->carve_out, which is a 8-bit integer. However, the sysfs interface allows setting it to a value larger than 255, resulting in an out-of-range update. atgc_age_threshold maps to {struct atgc_management}->age_threshold, which is a 64-bit integer, but its sysfs interface cannot correctly set values larger than UINT_MAX. The root causes are: 1. __sbi_store() treats all default values as unsigned int, which prevents updating integers larger than 4 bytes and causes out-of-bounds writes for integers smaller than 4 bytes. 2. f2fs_sbi_show() also assumes all default values are unsigned int, leading to out-of-bounds reads and incorrect access to integers larger than 4 bytes. This patch introduces {struct f2fs_attr}->size to record the actual size of the integer associated with each sysfs attribute. With this information, sysfs read and write operations can correctly access and update values according to their real data size, avoiding memory corruption and truncation.

HighCVSS 7.1 · v3.1—No exploit Fix available
Published
Mar 4, 2026
Updated
Jun 17, 2026
EPSS
0.1% · 7th percentile

Report tools

JSON

Action score

28

Monitor

Low priority for now.

CVSS
28 / 40 · 7.1 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

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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

Affected versions

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

  • linux linux kernel3.12 and later · before 5.10.251
  • linux linux kernel5.11 and later · before 5.15.201
  • linux linux kernel5.16 and later · before 6.1.164
  • linux linux kernel6.2 and later · before 6.6.127
  • linux linux kernel6.7 and later · before 6.12.74
  • linux linux kernel6.13 and later · before 6.18.13
  • linux linux kernel6.19 and later · before 6.19.3

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

    • 3.12affected
    • b59d0bae6ca30c496f298881616258f9cde0d9c6 and later · before e85a99db9ab85dfc30d93b0ca0e9156f3127f55aaffected · git
    • b59d0bae6ca30c496f298881616258f9cde0d9c6 and later · before 438a405fbad6882df0e34b3e1a16839a71f04240affected · git
    • b59d0bae6ca30c496f298881616258f9cde0d9c6 and later · before 6a6c07a9b49e43f0df42d7118fc76aa555c73d98affected · git
    • b59d0bae6ca30c496f298881616258f9cde0d9c6 and later · before eebd72cff518ac87e660aefb8a41224bd88c32ceaffected · git
    • b59d0bae6ca30c496f298881616258f9cde0d9c6 and later · before 4ef30b9f1641c9e877792df6b049f1cf507d002daffected · git
    • b59d0bae6ca30c496f298881616258f9cde0d9c6 and later · before d4a594dd952df123cbdcdee9b9640d9d55e4a954affected · git
    • b59d0bae6ca30c496f298881616258f9cde0d9c6 and later · before 3a905e183c047577b154f08a78ac3039e9454703affected · git
    • b59d0bae6ca30c496f298881616258f9cde0d9c6 and later · before 98ea0039dbfdd00e5cc1b9a8afa40434476c0955affected · git
    • before 3.12not affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:11linuxbefore 5.10.251-15.10.251-1
Debian:12linuxbefore 6.1.164-16.1.164-1
Debian:13linuxbefore 6.12.74-26.12.74-2
Debian:14linuxbefore 6.18.13-16.18.13-1

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-2026-23233Mar 4, 2026 · f2fs: fix to avoid mapping wrong physical block for swapfile
    31Monitor
  • ← EarlierCVE-2026-23234Mar 4, 2026 · f2fs: fix to avoid UAF in f2fs_write_end_io()
    31Monitor
  • Later →CVE-2026-23236Mar 4, 2026 · fbdev: smscufx: properly copy ioctl memory to kernelspace
    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 Linux3a905e183c047577b154f08a78ac3039e9454703Vendor (CNA)
Linux Linux438a405fbad6882df0e34b3e1a16839a71f04240Vendor (CNA)
Linux Linux4ef30b9f1641c9e877792df6b049f1cf507d002dVendor (CNA)
Linux Linux6a6c07a9b49e43f0df42d7118fc76aa555c73d98Vendor (CNA)
Linux Linux98ea0039dbfdd00e5cc1b9a8afa40434476c0955Vendor (CNA)
Linux Linuxd4a594dd952df123cbdcdee9b9640d9d55e4a954Vendor (CNA)
Linux Linuxe85a99db9ab85dfc30d93b0ca0e9156f3127f55aVendor (CNA)
Linux Linuxeebd72cff518ac87e660aefb8a41224bd88c32ceVendor (CNA)
debian:linux6.1.164-1 · 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
high · data can be read
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
High
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-125 · Out-of-bounds Read

CVSS vector

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

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓

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

References

Show all references (7 more)

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

All records