How severe is CVE-2021-47293?

CVE-2021-47293 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-2021-47293 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-2021-47293?

CVE-2021-47293 primarily affects Linux Linux Kernel. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-47293?

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-2021-47293 have an EU (EUVD) identifier?

Yes. CVE-2021-47293 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34298.

When was CVE-2021-47293 published?

CVE-2021-47293 was published on 2024-05-21 and last updated on 2026-06-17.

CVE-2021-47293

CVE-2021-47293 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.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 0% (14th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-34298
Affected product: Linux Linux Kernel
Published: 2024-05-21
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_skbmod: Skip non-Ethernet packets Currently tcf_skbmod_act() assumes that packets use Ethernet as their L2 protocol, which is not always the case. As an example, for CAN devices: $ ip link add dev vcan0 type vcan $ ip link set up vcan0 $ tc qdisc add dev vcan0 root handle 1: htb $ tc filter add dev vcan0 parent 1: protocol ip prio 10 \ matchall action skbmod swap mac Doing the above silently corrupts all the packets. Do not perform skbmod actions for non-Ethernet packets.

Frequently asked questions

What is CVE-2021-47293?: In the Linux kernel, the following vulnerability has been resolved: net/sched: act_skbmod: Skip non-Ethernet packets Currently tcf_skbmod_act() assumes that packets use Ethernet as their L2 protocol, which is not always the case. As an example, for CAN devices: $ ip link add dev vcan0 type vcan $ ip link set up vcan0 $ tc qdisc add dev vcan0 root handle 1: htb $ tc filter add dev vcan0 parent 1: protocol ip prio 10 \ matchall action skbmod swap mac Doing the above silently corrupts all the packets. Do not perform skbmod actions for non-Ethernet packets.
How severe is CVE-2021-47293?: CVE-2021-47293 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-2021-47293 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-2021-47293?: CVE-2021-47293 primarily affects Linux Linux Kernel. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-47293?: 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-2021-47293 have an EU (EUVD) identifier?: Yes. CVE-2021-47293 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34298.
When was CVE-2021-47293 published?: CVE-2021-47293 was published on 2024-05-21 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.14:rc2:*:*:*:*:*:*

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