How severe is CVE-2021-47164?

CVE-2021-47164 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-2021-47164 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47164?

CVE-2021-47164 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-47164?

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

Does CVE-2021-47164 have an EU (EUVD) identifier?

Yes. CVE-2021-47164 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33812.

When was CVE-2021-47164 published?

CVE-2021-47164 was published on 2024-03-25 and last updated on 2026-06-17.

CVE-2021-47164

CVE-2021-47164 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-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (14th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-33812
Weakness: CWE-476
Affected product: Linux Linux Kernel
Published: 2024-03-25
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix null deref accessing lag dev It could be the lag dev is null so stop processing the event. In bond_enslave() the active/backup slave being set before setting the upper dev so first event is without an upper dev. After setting the upper dev with bond_master_upper_dev_link() there is a second event and in that event we have an upper dev.

Frequently asked questions

What is CVE-2021-47164?: In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix null deref accessing lag dev It could be the lag dev is null so stop processing the event. In bond_enslave() the active/backup slave being set before setting the upper dev so first event is without an upper dev. After setting the upper dev with bond_master_upper_dev_link() there is a second event and in that event we have an upper dev.
How severe is CVE-2021-47164?: CVE-2021-47164 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-2021-47164 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47164?: CVE-2021-47164 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-47164?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47164 have an EU (EUVD) identifier?: Yes. CVE-2021-47164 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33812.
When was CVE-2021-47164 published?: CVE-2021-47164 was published on 2024-03-25 and last updated on 2026-06-17.

References

Affected products (1)

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

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