How severe is CVE-2026-53231?

CVE-2026-53231 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-53231 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-53231?

CVE-2026-53231 primarily affects Linux Linux Kernel. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-53231?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-53231 have an EU (EUVD) identifier?

Yes. CVE-2026-53231 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39322.

When was CVE-2026-53231 published?

CVE-2026-53231 was published on 2026-06-25 and last updated on 2026-07-02.

CVE-2026-53231

CVE-2026-53231 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-667.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (1st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-39322
Weakness: CWE-667
Affected product: Linux Linux Kernel
Published: 2026-06-25
Last modified: 2026-07-02

Description

In the Linux kernel, the following vulnerability has been resolved: net: phy: don't try to setup PHY-driven SFP cages when using genphy We don't have support for PHY-driver SFP cages with the genphy code. On top of that, it was found by sashiko that running sfp_bus_add_upstream() for genphy deadlocks, as for genphy the PHY probing runs under RTNL, which isn't the case for non-genphy drivers. This problem was reproduced, and does lead to a deadlock on RTNL. Before the blamed commit, the phy_sfp_probe() call was made by individual PHY drivers, so there was no way to get to the SFP probing path when using genphy. Let's therefore only run phy_sfp_probe when not using genphy.

Frequently asked questions

What is CVE-2026-53231?: In the Linux kernel, the following vulnerability has been resolved: net: phy: don't try to setup PHY-driven SFP cages when using genphy We don't have support for PHY-driver SFP cages with the genphy code. On top of that, it was found by sashiko that running sfp_bus_add_upstream() for genphy deadlocks, as for genphy the PHY probing runs under RTNL, which isn't the case for non-genphy drivers. This problem was reproduced, and does lead to a deadlock on RTNL. Before the blamed commit, the phy_sfp_probe() call was made by individual PHY drivers, so there was no way to get to the SFP probing path when using genphy. Let's therefore only run phy_sfp_probe when not using genphy.
How severe is CVE-2026-53231?: CVE-2026-53231 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-53231 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-53231?: CVE-2026-53231 primarily affects Linux Linux Kernel. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-53231?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-53231 have an EU (EUVD) identifier?: Yes. CVE-2026-53231 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39322.
When was CVE-2026-53231 published?: CVE-2026-53231 was published on 2026-06-25 and last updated on 2026-07-02.

References

Affected products (8)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:*

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