Vulnerability-Lookup

FKIE_CVE-2025-39925

Vulnerability from fkie_nvd - Published: 2025-10-01 08:15 - Updated: 2026-01-14 18:16

Severity ?

5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: can: j1939: implement NETDEV_UNREGISTER notification handler syzbot is reporting unregister_netdevice: waiting for vcan0 to become free. Usage count = 2 problem, for j1939 protocol did not have NETDEV_UNREGISTER notification handler for undoing changes made by j1939_sk_bind(). Commit 25fe97cb7620 ("can: j1939: move j1939_priv_put() into sk_destruct callback") expects that a call to j1939_priv_put() can be unconditionally delayed until j1939_sk_sock_destruct() is called. But we need to call j1939_priv_put() against an extra ref held by j1939_sk_bind() call (as a part of undoing changes made by j1939_sk_bind()) as soon as NETDEV_UNREGISTER notification fires (i.e. before j1939_sk_sock_destruct() is called via j1939_sk_release()). Otherwise, the extra ref on "struct j1939_priv" held by j1939_sk_bind() call prevents "struct net_device" from dropping the usage count to 1; making it impossible for unregister_netdevice() to continue. [mkl: remove space in front of label]

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/7fcbe5b2c6a4b5407bf2241fdb71e0a390f6ab9a	Patch
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/da9e8f429139928570407e8f90559b5d46c20262	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	6.17
linux	linux_kernel	6.17
linux	linux_kernel	6.17
linux	linux_kernel	6.17
linux	linux_kernel	6.17

JSON

To clipboard

{
  "configurations": [
    {
      "nodes": [
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          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "6EFB31B6-1E03-4B23-85D7-3E0CA07C153F",
              "versionEndExcluding": "6.16.8",
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              "vulnerable": true
            },
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              "vulnerable": true
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    }
  ],
  "id": "CVE-2025-39925",
  "lastModified": "2026-01-14T18:16:40.930",
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CVE-2025-39925 (GCVE-0-2025-39925)

Vulnerability from cvelistv5 – Published: 2025-10-01 08:07 – Updated: 2026-01-14 17:42

Title

can: j1939: implement NETDEV_UNREGISTER notification handler

Summary

Severity ?

5.5 (Medium)


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

CWE

CWE-noinfo Not enough information

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/da9e8f42913992857…
	https://git.kernel.org/stable/c/7fcbe5b2c6a4b5407…

Impacted products

Vendor

Product

Version

Linux

Affected: 9d71dd0c70099914fcd063135da3c580865e924c , < da9e8f429139928570407e8f90559b5d46c20262 (git)
Affected: 9d71dd0c70099914fcd063135da3c580865e924c , < 7fcbe5b2c6a4b5407bf2241fdb71e0a390f6ab9a (git)

Linux

Affected: 5.4
Unaffected: 0 , < 5.4 (semver)
Unaffected: 6.16.8 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2025-39925

CVE-2025-39925 (GCVE-0-2025-39925)

Tags

Sightings

Nomenclature