How severe is CVE-2021-46991?

CVE-2021-46991 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-46991 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-46991?

CVE-2021-46991 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-46991?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2021-46991 have an EU (EUVD) identifier?

Yes. CVE-2021-46991 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33639.

When was CVE-2021-46991 published?

CVE-2021-46991 was published on 2024-02-28 and last updated on 2026-06-17.

CVE-2021-46991

CVE-2021-46991 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.8. 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-416.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-33639
Weakness: CWE-416
Affected product: Linux Linux Kernel
Published: 2024-02-28
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: i40e: Fix use-after-free in i40e_client_subtask() Currently the call to i40e_client_del_instance frees the object pf->cinst, however pf->cinst->lan_info is being accessed after the free. Fix this by adding the missing return. Addresses-Coverity: ("Read from pointer after free")

Frequently asked questions

What is CVE-2021-46991?: In the Linux kernel, the following vulnerability has been resolved: i40e: Fix use-after-free in i40e_client_subtask() Currently the call to i40e_client_del_instance frees the object pf->cinst, however pf->cinst->lan_info is being accessed after the free. Fix this by adding the missing return. Addresses-Coverity: ("Read from pointer after free")
How severe is CVE-2021-46991?: CVE-2021-46991 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-46991 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-46991?: CVE-2021-46991 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-46991?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2021-46991 have an EU (EUVD) identifier?: Yes. CVE-2021-46991 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33639.
When was CVE-2021-46991 published?: CVE-2021-46991 was published on 2024-02-28 and last updated on 2026-06-17.

References

Affected products (1)

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

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