CVE-2026-53231

System hang via genphy SFP deadlock

Published Jun 25, 2026 · Updated Jun 25, 2026

Improper locking in the Linux Kernel 7.0 through 7.0.12 PHY subsystem allows local users to hang the system through a genphy-managed SFP cage. The PHY probe path calls sfp_bus_add_upstream() while generic-PHY probing already holds RTNL, and the nested path deadlocks on that lock. Reachability requires local control of a PHY-driven SFP configuration using genphy; the resulting RTNL deadlock interrupts networking and can hang the host.

CVSS severityUnavailable
Unscored
EPSS probability0.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper locking in the Linux Kernel 7.0 through 7.0.12 PHY subsystem allows local users to hang the system through a genphy-managed SFP cage. The PHY probe path calls sfp_bus_add_upstream() while generic-PHY probing already holds RTNL, and the nested path deadlocks on that lock. Reachability requires local control of a PHY-driven SFP configuration using genphy; the resulting RTNL deadlock interrupts networking and can hang the host.

The record

CVE
CVE-2026-53231
Published
Jun 25, 2026
Updated
Jun 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=7.0
  2. Affected versionversion=bad869b5e41a08424ff130fd6bb41b854be70095 <5a0082ec20a05ef2378410323a5089a8f1786f4a
  3. Affected versionversion=bad869b5e41a08424ff130fd6bb41b854be70095 <ef8d739eee6f85303cbecebc01eb72f063de74e0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=7.0; version=bad869b5e41a08424ff130fd6bb41b854be70095 <5a0082ec20a05ef2378410323a5089a8f1786f4a; version=bad869b5e41a08424ff130fd6bb41b854be70095 <ef8d739eee6f85303cbecebc01eb72f063de74e0

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo