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NVD / CVE Program· CNA Linux

CVE-2025-39954: clk: sunxi-ng: mp: Fix dual-divider clock rate readback

MediumCVSS 5.5 · v3.1—No exploit Fix available

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: 0.13% (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 25fbbaf515acd13399589bd5ee6de5f35740cef2, 40108f69c372af3aea73e7829d6849a44638d662.

Low priority for now. Upgrade to Linux Linux 25fbbaf515acd13399589bd5ee6de5f35740cef2, 40108f69c372af3aea73e7829d6849a44638d662 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: clk: sunxi-ng: mp: Fix dual-divider clock rate readback When dual-divider clock support was introduced, the P divider offset was left out of the .recalc_rate readback function. This causes the clock rate to become bogus or even zero (possibly due to the P divider being 1, leading to a divide-by-zero). Fix this by incorporating the P divider offset into the calculation.

Published
Oct 9, 2025
Updated
Oct 19, 2026
EPSS
0.1% · 2th percentile

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

  • 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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  • when exploit code appears or is weaponized
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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

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

    • 6.15affected
    • 45717804b75eda8a76eacc04509ca4d68dd2caaf and later · before 40108f69c372af3aea73e7829d6849a44638d662affected · git
    • 45717804b75eda8a76eacc04509ca4d68dd2caaf and later · before 25fbbaf515acd13399589bd5ee6de5f35740cef2affected · git
    • before 6.15not affected · semver
    • 6.16.9 and later · up to and including 6.16.*not affected · semver
    • 6.17 and laternot affected · original_commit_for_fix

Affected versions

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

  • linux linux kernel6.15 and later · before 6.16.9
  • linux linux kernel6.17

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:14linuxbefore 6.16.9-16.16.9-1

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-2023-53686Oct 7, 2025 · net/handshake: fix null-ptr-deref in handshake_nl_done_doit()
    22Monitor
  • ← EarlierCVE-2023-53687Oct 7, 2025 · tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() when iterating clk
    22Monitor
  • Later →CVE-2025-39955Oct 9, 2025 · tcp: Clear tcp_sk(sk)->fastopen_rsk in tcp_disconnect().
    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 Linux25fbbaf515acd13399589bd5ee6de5f35740cef2Vendor (CNA)
Linux Linux40108f69c372af3aea73e7829d6849a44638d662Vendor (CNA)
debian:linux6.16.9-1 · 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.

Variant candidates

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

  • CVE-2024-26945526 days apartcrypto: iaa - Fix nr_cpus < nr_iaa case
    33Monitor
  • CVE-2025-399098 days apartmm/damon/lru_sort: avoid divide-by-zero in damon_lru_sort_apply_parameters()
    22Monitor
  • CVE-2025-399168 days apartmm/damon/reclaim: avoid divide-by-zero in damon_reclaim_apply_parameters()
    22Monitor
  • CVE-2025-3974228 days apartRDMA: hfi1: fix possible divide-by-zero in find_hw_thread_mask()
    22Monitor
  • CVE-2025-3871935 days apartnet: hibmcge: fix the division by zero issue
    22Monitor
  • CVE-2025-3851954 days apartmm/damon: fix divide by zero in damon_get_intervals_score()
    22Monitor

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · public bounty program.

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)

CWE-369 · Divide By Zero

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.

References

Show all references (1 more)

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

All records