How severe is CVE-2021-46973?

CVE-2021-46973 has a CVSS 3.x base score of 8.4, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-46973 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-2021-46973?

CVE-2021-46973 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-46973?

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-2021-46973 have an EU (EUVD) identifier?

Yes. CVE-2021-46973 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33621.

When was CVE-2021-46973 published?

CVE-2021-46973 was published on 2024-02-27 and last updated on 2026-06-17.

CVE-2021-46973

CVE-2021-46973 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 8.4. 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 8.4)
EPSS exploit prediction: 0% (14th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-33621
Weakness: CWE-416
Affected product: Linux Linux Kernel
Published: 2024-02-27
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: net: qrtr: Avoid potential use after free in MHI send It is possible that the MHI ul_callback will be invoked immediately following the queueing of the skb for transmission, leading to the callback decrementing the refcount of the associated sk and freeing the skb. As such the dereference of skb and the increment of the sk refcount must happen before the skb is queued, to avoid the skb to be used after free and potentially the sk to drop its last refcount..

Frequently asked questions

What is CVE-2021-46973?: In the Linux kernel, the following vulnerability has been resolved: net: qrtr: Avoid potential use after free in MHI send It is possible that the MHI ul_callback will be invoked immediately following the queueing of the skb for transmission, leading to the callback decrementing the refcount of the associated sk and freeing the skb. As such the dereference of skb and the increment of the sk refcount must happen before the skb is queued, to avoid the skb to be used after free and potentially the sk to drop its last refcount..
How severe is CVE-2021-46973?: CVE-2021-46973 has a CVSS 3.x base score of 8.4, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-46973 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-2021-46973?: CVE-2021-46973 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-46973?: 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-2021-46973 have an EU (EUVD) identifier?: Yes. CVE-2021-46973 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33621.
When was CVE-2021-46973 published?: CVE-2021-46973 was published on 2024-02-27 and last updated on 2026-06-17.

References

Affected products (1)

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

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