How severe is CVE-2021-43267?

CVE-2021-43267 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-43267 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 58% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43267?

CVE-2021-43267 primarily affects Linux Linux Kernel. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-43267?

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

When was CVE-2021-43267 published?

CVE-2021-43267 was published on 2021-11-02 and last updated on 2026-06-17.

CVE-2021-43267

CVE-2021-43267 is a critical-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 58% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-1284.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 58% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1284
Affected product: Linux Linux Kernel
Published: 2021-11-02
Last modified: 2026-06-17

Description

An issue was discovered in net/tipc/crypto.c in the Linux kernel before 5.14.16. The Transparent Inter-Process Communication (TIPC) functionality allows remote attackers to exploit insufficient validation of user-supplied sizes for the MSG_CRYPTO message type.

Frequently asked questions

What is CVE-2021-43267?: An issue was discovered in net/tipc/crypto.c in the Linux kernel before 5.14.16. The Transparent Inter-Process Communication (TIPC) functionality allows remote attackers to exploit insufficient validation of user-supplied sizes for the MSG_CRYPTO message type.
How severe is CVE-2021-43267?: CVE-2021-43267 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-43267 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 58% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43267?: CVE-2021-43267 primarily affects Linux Linux Kernel. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-43267?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-43267 published?: CVE-2021-43267 was published on 2021-11-02 and last updated on 2026-06-17.

References

Affected products (10)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*

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