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NVD / CVE Program· CNA Linux

CVE-2025-38305: ptp: remove ptp->n_vclocks check logic in ptp_vclock_in_use()

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: 0.17% (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 259119595227fd20f6aa29d85abe086b6fdd9eb1, 5d217e7031a5c06d366580fc6ddbf43527b780d4, 87f7ce260a3c838b49e1dc1ceedf1006795157a2; azl3 kernel 6.6.92.2-2 on Azure Linux 3.0 6.6.96.1-1.

Low priority for now. Upgrade to Linux Linux 259119595227fd20f6aa29d85abe086b6fdd9eb1, 5d217e7031a5c06d366580fc6ddbf43527b780d4, 87f7ce260a3c838b49e1dc1ceedf1006795157a2; 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: ptp: remove ptp->n_vclocks check logic in ptp_vclock_in_use() There is no disagreement that we should check both ptp->is_virtual_clock and ptp->n_vclocks to check if the ptp virtual clock is in use. However, when we acquire ptp->n_vclocks_mux to read ptp->n_vclocks in ptp_vclock_in_use(), we observe a recursive lock in the call trace starting from n_vclocks_store(). ============================================ WARNING: possible recursive locking detected 6.15.0-rc6 #1 Not tainted -------------------------------------------- syz.0.1540/13807 is trying to acquire lock: ffff888035a24868 (&ptp->n_vclocks_mux){+.+.}-{4:4}, at: ptp_vclock_in_use drivers/ptp/ptp_private.h:103 [inline] ffff888035a24868 (&ptp->n_vclocks_mux){+.+.}-{4:4}, at: ptp_clock_unregister+0x21/0x250 drivers/ptp/ptp_clock.c:415 but task is already holding lock: ffff888030704868 (&ptp->n_vclocks_mux){+.+.}-{4:4}, at: n_vclocks_store+0xf1/0x6d0 drivers/ptp/ptp_sysfs.c:215 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&ptp->n_vclocks_mux); lock(&ptp->n_vclocks_mux); *** DEADLOCK *** .... ============================================ The best way to solve this is to remove the logic that checks ptp->n_vclocks in ptp_vclock_in_use(). The reason why this is appropriate is that any path that uses ptp->n_vclocks must unconditionally check if ptp->n_vclocks is greater than 0 before unregistering vclocks, and all functions are already written this way. And in the function that uses ptp->n_vclocks, we already get ptp->n_vclocks_mux before unregistering vclocks. Therefore, we need to remove the redundant check for ptp->n_vclocks in ptp_vclock_in_use() to prevent recursive locking.

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
Jul 10, 2025
Updated
Jun 17, 2026
EPSS
0.1% · 7th 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

  • 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 you'll hear from us

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  • when exploit code appears or is weaponized
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  • 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
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 kernel5.16 and later · before 6.1.142
  • linux linux kernel6.2 and later · before 6.6.94
  • linux linux kernel6.7 and later · before 6.12.34
  • linux linux kernel5.14.1 and later · before 5.15.186
  • linux linux kernel6.13 and later · before 6.15.3
  • linux linux kernel5.14
  • linux linux kernel6.16

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

    • 5.14affected
    • 73f37068d540eba5f93ba3a0019bf479d35ebd76 and later · before 5d217e7031a5c06d366580fc6ddbf43527b780d4affected · git
    • 73f37068d540eba5f93ba3a0019bf479d35ebd76 and later · before b1b73c452331451020be3bf4b014901015ae6663affected · git
    • 73f37068d540eba5f93ba3a0019bf479d35ebd76 and later · before 259119595227fd20f6aa29d85abe086b6fdd9eb1affected · git
    • 73f37068d540eba5f93ba3a0019bf479d35ebd76 and later · before b93e6fef4eda48e17d9c642b9abad98a066fd4a3affected · git
    • 73f37068d540eba5f93ba3a0019bf479d35ebd76 and later · before ef8fc007c28a30a4c0d90bf755e0f343d99bb392affected · git
    • 73f37068d540eba5f93ba3a0019bf479d35ebd76 and later · before 87f7ce260a3c838b49e1dc1ceedf1006795157a2affected · git
    • before 5.14not affected · semver
    • 5.15.186 and later · up to and including 5.15.*not affected · semver
    • 6.1.142 and later · up to and including 6.1.*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-2025-38302Jul 10, 2025 · block: don't use submit_bio_noacct_nocheck in blk_zone_wplug_bio_work
    22Monitor
  • ← EarlierCVE-2025-38304Jul 10, 2025 · Bluetooth: Fix NULL pointer deference on eir_get_service_data
    22Monitor
  • Later →CVE-2025-38306Jul 10, 2025 · fs/fhandle.c: fix a race in call of has_locked_children()
    18Monitor

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 Linux259119595227fd20f6aa29d85abe086b6fdd9eb1Vendor (CNA)
Linux Linux5d217e7031a5c06d366580fc6ddbf43527b780d4Vendor (CNA)
Linux Linux87f7ce260a3c838b49e1dc1ceedf1006795157a2Vendor (CNA)
Linux Linuxb1b73c452331451020be3bf4b014901015ae6663Vendor (CNA)
Linux Linuxb93e6fef4eda48e17d9c642b9abad98a066fd4a3Vendor (CNA)
Linux Linuxef8fc007c28a30a4c0d90bf755e0f343d99bb392Vendor (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 (6 more)

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

All records