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NVD / CVE Program· CNA Linux

CVE-2026-64159: netfs: Fix zeropoint update where i_size > remote_i_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: 0.16% (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 4543a4d737944134a1394afe797622546fbcc98a, 5afc2d9b86bed2e4d9e1ba467790cbc793223f98, 5cd5207de519ef0c085f4f559adf5eefcb4c5202.

Low priority for now. Upgrade to Linux Linux 4543a4d737944134a1394afe797622546fbcc98a, 5afc2d9b86bed2e4d9e1ba467790cbc793223f98, 5cd5207de519ef0c085f4f559adf5eefcb4c5202 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: netfs: Fix zeropoint update where i_size > remote_i_size Fix the update of the zero point[*] by netfs_release_folio() when there is uncommitted data in the pagecache beyond the folio being released but the on-server EOF is in this folio (ie. i_size > remote_i_size). The update needs to limit zero_point to remote_i_size, not i_size as i_size is a local phenomenon reflecting updates made locally to the pagecache, not stuff written to the server. remote_i_size tracks the server's i_size. [*] The zero point is the file position from which we can assume that the server will just return zeros, so we can avoid generating reads. Note that netfs_invalidate_folio() probably doesn't need fixing as zero_point should be updated by setattr after truncation or fallocate. Found with: fsx -q -N 1000000 -p 10000 -o 128000 -l 600000 \ /xfstest.test/junk --replay-ops=junk.fsxops using the following as junk.fsxops: truncate 0x0 0x1bbae 0x82864 write 0x3ef2e 0xf9c8 0x1bbae write 0x67e05 0xcb5a 0x4e8f6 mapread 0x57781 0x85b6 0x7495f copy_range 0x5d3d 0x10329 0x54fac 0x7495f write 0x64710 0x1c2b 0x7495f mapread 0x64000 0x1000 0x7495f on cifs with the default cache option. It shows read-gaps on folio 0x64 failing with a short read (ie. it hits EOF) if the FMODE_READ check is commented out in netfs_perform_write(): if (//(file->f_mode & FMODE_READ) || netfs_is_cache_enabled(ctx)) { and no fscache. This was initially found with the generic/522 xfstest.

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
Jul 19, 2026
Updated
Oct 21, 2026
EPSS
0.1% · 5th 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%

Get told when this record changes

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  • 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 kernel6.10.8 and later · before 6.11
  • linux linux kernel6.11.1 and later · before 7.0.11
  • linux linux kernel6.11
  • linux linux kernel7.1

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

    • e2814004138a541110d4b2dc254a8f619c2c4ce0, 6.11affected
    • cce6bfa6ca0e30af9927b0074c97fe6a92f28092 and later · before f706e3889ff75877ecb3abae5ad667dbc990331eaffected · git
    • cce6bfa6ca0e30af9927b0074c97fe6a92f28092 and later · before 5afc2d9b86bed2e4d9e1ba467790cbc793223f98affected · git
    • cce6bfa6ca0e30af9927b0074c97fe6a92f28092 and later · before 5cd5207de519ef0c085f4f559adf5eefcb4c5202affected · git
    • cce6bfa6ca0e30af9927b0074c97fe6a92f28092 and later · before 4543a4d737944134a1394afe797622546fbcc98aaffected · git
    • 6.10.8 and later · before 6.11affected · semver
    • before 6.11not affected · semver
    • 6.12.114 and later · up to and including 6.12.*not affected · semver
    • 6.18.57 and later · up to and including 6.18.*not affected · semver
    • 7.0.11 and later · up to and including 7.0.*not affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:13linuxbefore 6.12.115-26.12.115-2
Debian:14linuxbefore 7.0.12-17.0.12-1

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-2026-64146Jul 19, 2026 · erofs: fix metabuf leak in inode xattr initialization
    22Monitor
  • ← EarlierCVE-2026-64154Jul 19, 2026 · drm/msm/adreno: Fix a reference leak in a6xx_gpu_init()
    22Monitor
  • Later →CVE-2026-64160Jul 19, 2026 · netfs: Fix potential for tearing in ->remote_i_size and ->zero_point
    39Monitor

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 Linux4543a4d737944134a1394afe797622546fbcc98aVendor (CNA)
Linux Linux5afc2d9b86bed2e4d9e1ba467790cbc793223f98Vendor (CNA)
Linux Linux5cd5207de519ef0c085f4f559adf5eefcb4c5202Vendor (CNA)
Linux Linux6.11Vendor (CNA)
Linux Linuxf706e3889ff75877ecb3abae5ad667dbc990331eVendor (CNA)
debian:linux6.12.115-2 · Debian:13Package registry (OSV)
debian:linux7.0.12-1 · Debian:14Package 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.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

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 (3 more)

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

All records