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NVD / CVE Program· CNA Linux

CVE-2025-37956: ksmbd: prevent rename with empty string

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: 0.38% (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 35e2964e93d95185d2db0c0ffd9959d0197b3956, 53e3e5babc0963a92d856a5ec0ce92c59f54bc12, 6ee551672c8cf36108b0cfba92ec0c7c28ac3439; azl3 kernel 6.6.85.1-4 on Azure Linux 3.0 6.6.92.2-1; azl3 kernel 6.6.92.2-1 on Azure Linux 3.0 6.6.92.2-1.
  • Severity is disputed: the assigning authority (CNA) scores it 8.8, NVD 5.5.

Low priority for now. Upgrade to Linux Linux 35e2964e93d95185d2db0c0ffd9959d0197b3956, 53e3e5babc0963a92d856a5ec0ce92c59f54bc12, 6ee551672c8cf36108b0cfba92ec0c7c28ac3439; azl3 kernel 6.6.85.1-4 on Azure Linux 3.0 6.6.92.2-1; azl3 kernel 6.6.92.2-1 on Azure Linux 3.0 6.6.92.2-1 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: ksmbd: prevent rename with empty string Client can send empty newname string to ksmbd server. It will cause a kernel oops from d_alloc. This patch return the error when attempting to rename a file or directory with an empty new name string.

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
May 20, 2025
Updated
Oct 30, 2026
EPSS
0.3% · 32th 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 · 0.3%

CNA vs NVD score

NVD
5.5
CNA · Linux
8.8
3.3 point gap

CVSS:3.1/AV:N/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.

Get told when this record changes

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

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2025-37956

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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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 kernel5.15 and later · before 6.6.91
  • linux linux kernel6.7 and later · before 6.12.29
  • linux linux kernel6.13 and later · before 6.14.7
  • linux linux kernel6.15

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

    • 5.15affected
    • 0626e6641f6b467447c81dd7678a69c66f7746cf and later · before 35e2964e93d95185d2db0c0ffd9959d0197b3956affected · git
    • 0626e6641f6b467447c81dd7678a69c66f7746cf and later · before 6ee551672c8cf36108b0cfba92ec0c7c28ac3439affected · git
    • 0626e6641f6b467447c81dd7678a69c66f7746cf and later · before c57301e332cc413fe0a7294a90725f4e21e9549daffected · git
    • 0626e6641f6b467447c81dd7678a69c66f7746cf and later · before d7f2c00acb1ef64304fd40ac507e9213ff1d9b5caffected · git
    • 0626e6641f6b467447c81dd7678a69c66f7746cf and later · before 53e3e5babc0963a92d856a5ec0ce92c59f54bc12affected · git
    • before 5.15not affected · semver
    • 6.1.191 and later · up to and including 6.1.*not affected · semver
    • 6.6.91 and later · up to and including 6.6.*not affected · semver
    • 6.12.29 and later · up to and including 6.12.*not affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12linuxfrom 0—
Debian:13linuxbefore 6.12.29-16.12.29-1

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-2025-37952May 20, 2025 · ksmbd: Fix UAF in __close_file_table_ids
    31Monitor
  • ← EarlierCVE-2025-37954May 20, 2025 · smb: client: Avoid race in open_cached_dir with lease breaks
    22Monitor
  • Later →CVE-2025-37957May 20, 2025 · KVM: SVM: Forcibly leave SMM mode on SHUTDOWN interception
    31Monitor

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 Linux35e2964e93d95185d2db0c0ffd9959d0197b3956Vendor (CNA)
Linux Linux53e3e5babc0963a92d856a5ec0ce92c59f54bc12Vendor (CNA)
Linux Linux6ee551672c8cf36108b0cfba92ec0c7c28ac3439Vendor (CNA)
Linux Linuxc57301e332cc413fe0a7294a90725f4e21e9549dVendor (CNA)
Linux Linuxd7f2c00acb1ef64304fd40ac507e9213ff1d9b5cVendor (CNA)
azl3 kernel 6.6.85.1-4 on Azure Linux 3.06.6.92.2-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
azl3 kernel 6.6.92.2-1 on Azure Linux 3.06.6.92.2-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:linux6.12.29-1 · Debian:13Package 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 (4 more)

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

All records