LiveActive security incident?Get immediate response
CVE Record

CVE-2022-48961: net: mdio: fix unbalanced fwnode reference count in mdio_device_release()

In the Linux kernel, the following vulnerability has been resolved: net: mdio: fix unbalanced fwnode reference count in mdio_device_release() There is warning report about of_node refcount leak while probing mdio device: OF: ERROR: memory leak, expected refcount 1 instead of 2, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node /spi/soc@0/mdio@710700c0/ethernet@4 In of_mdiobus_register_device(), we increase fwnode refcount by fwnode_handle_get() before associating the of_node with mdio device, but it has never been decreased in normal path. Since that, in mdio_device_release(), it needs to call fwnode_handle_put() in addition instead of calling kfree() directly. After above, just calling mdio_device_free() in the error handle path of of_mdiobus_register_device() is enough to keep the refcount balanced.

UnknownCVSS not scoredNot KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

This is a Linux kernel resource-management flaw in MDIO device cleanup. The source describes an unbalanced firmware-node reference count that can cause memory-leak warnings during MDIO device probing. It appears most relevant to embedded or network-oriented Linux systems using MDIO and device-tree overlays.

Executive priority

Treat this as a targeted kernel maintenance issue unless your fleet includes embedded networking systems or custom Linux images. There is no source-backed evidence of active exploitation, but affected kernels should still be updated through normal patch cycles.

Technical view

In of_mdiobus_register_device(), fwnode_handle_get() increments the node reference before association with an MDIO device. The normal release path did not balance that reference. The fix changes mdio_device_release() to use fwnode_handle_put(), and simplifies error handling through mdio_device_free().

Likely exposure

Exposure is likely limited to Linux kernels exercising the MDIO bus registration path, especially systems with MDIO-connected Ethernet hardware or device-tree overlay workflows. The source bundle does not establish broad server or desktop impact, exact distro package exposure, or runtime exploitability.

Exploitation context

The CVE is not listed as KEV in the provided bundle, and no cited source states active exploitation or a public exploit. The available evidence describes a kernel reference-count leak and warning condition, not a demonstrated privilege escalation or remote attack path.

Researcher notes

The record lacks CVSS, CWE, detailed version ranges, and exploitability analysis. Validation should focus on whether the MDIO release path contains the fwnode_handle_put() fix, and whether local kernel builds or vendor packages backported the stable patches.

Mitigation direction

  • Apply Linux stable or distro kernel updates that include the referenced fixes.
  • Check vendor or distribution advisories for exact fixed package versions.
  • Prioritize embedded, appliance, and network systems using MDIO hardware paths.
  • If updates are unavailable, monitor vendor guidance for supported backports or mitigations.

Validation and detection

  • Inventory Linux kernel versions on systems with MDIO or device-tree overlay use.
  • Confirm the running kernel includes one of the referenced stable commits or vendor backport.
  • Review kernel logs for OF refcount or memory leak warnings during MDIO probing.
  • Track affected assets until fixed distro packages are installed and rebooted.
Prepared
Confidence
medium
Sources
5

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cve · low confidence lookup

CVE-2022-48961 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
3Timeline events
1ADP providers
4Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: partial

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinuxa9049e0c513c4521dbfaa302af8ed08b3366b41f, a9049e0c513c4521dbfaa302af8ed08b3366b41f, a9049e0c513c4521dbfaa302af8ed08b3366b41funaffected
LinuxLinux4.5, 0, 5.15.83, 6.0.13, 6.1affected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.