How severe is CVE-2026-31621?

CVE-2026-31621 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-2026-31621 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-31621?

CVE-2026-31621 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-31621?

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

Does CVE-2026-31621 have an EU (EUVD) identifier?

Yes. CVE-2026-31621 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25514.

When was CVE-2026-31621 published?

CVE-2026-31621 was published on 2026-04-24 and last updated on 2026-06-17.

CVE-2026-31621

CVE-2026-31621 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-908.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (2nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-25514
Weakness: CWE-908
Affected product: Linux Linux Kernel
Published: 2026-04-24
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: bnge: return after auxiliary_device_uninit() in error path When auxiliary_device_add() fails, the error block calls auxiliary_device_uninit() but does not return. The uninit drops the last reference and synchronously runs bnge_aux_dev_release(), which sets bd->auxr_dev = NULL and frees the underlying object. The subsequent bd->auxr_dev->net = bd->netdev then dereferences NULL, which is not a good thing to have happen when trying to clean up from an error. Add the missing return, as the auxiliary bus documentation states is a requirement (seems that LLM tools read documentation better than humans do...)

Frequently asked questions

What is CVE-2026-31621?: In the Linux kernel, the following vulnerability has been resolved: bnge: return after auxiliary_device_uninit() in error path When auxiliary_device_add() fails, the error block calls auxiliary_device_uninit() but does not return. The uninit drops the last reference and synchronously runs bnge_aux_dev_release(), which sets bd->auxr_dev = NULL and frees the underlying object. The subsequent bd->auxr_dev->net = bd->netdev then dereferences NULL, which is not a good thing to have happen when trying to clean up from an error. Add the missing return, as the auxiliary bus documentation states is a requirement (seems that LLM tools read documentation better than humans do...)
How severe is CVE-2026-31621?: CVE-2026-31621 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-2026-31621 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-31621?: CVE-2026-31621 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-31621?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-31621 have an EU (EUVD) identifier?: Yes. CVE-2026-31621 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25514.
When was CVE-2026-31621 published?: CVE-2026-31621 was published on 2026-04-24 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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