How severe is CVE-2021-4441?

CVE-2021-4441 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-2021-4441 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4441?

CVE-2021-4441 primarily affects Linux Linux Kernel. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-4441?

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

Does CVE-2021-4441 have an EU (EUVD) identifier?

Yes. CVE-2021-4441 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34640.

When was CVE-2021-4441 published?

CVE-2021-4441 was published on 2024-08-22 and last updated on 2026-06-17.

CVE-2021-4441

CVE-2021-4441 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% (13th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-34640
Weakness: CWE-476
Affected product: Linux Linux Kernel
Published: 2024-08-22
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: spi: spi-zynq-qspi: Fix a NULL pointer dereference in zynq_qspi_exec_mem_op() In zynq_qspi_exec_mem_op(), kzalloc() is directly used in memset(), which could lead to a NULL pointer dereference on failure of kzalloc(). Fix this bug by adding a check of tmpbuf. This bug was found by a static analyzer. The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs. Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug. Builds with CONFIG_SPI_ZYNQ_QSPI=m show no new warnings, and our static analyzer no longer warns about this code.

Frequently asked questions

What is CVE-2021-4441?: In the Linux kernel, the following vulnerability has been resolved: spi: spi-zynq-qspi: Fix a NULL pointer dereference in zynq_qspi_exec_mem_op() In zynq_qspi_exec_mem_op(), kzalloc() is directly used in memset(), which could lead to a NULL pointer dereference on failure of kzalloc(). Fix this bug by adding a check of tmpbuf. This bug was found by a static analyzer. The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs. Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug. Builds with CONFIG_SPI_ZYNQ_QSPI=m show no new warnings, and our static analyzer no longer warns about this code.
How severe is CVE-2021-4441?: CVE-2021-4441 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-2021-4441 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4441?: CVE-2021-4441 primarily affects Linux Linux Kernel. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-4441?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-4441 have an EU (EUVD) identifier?: Yes. CVE-2021-4441 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34640.
When was CVE-2021-4441 published?: CVE-2021-4441 was published on 2024-08-22 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.17:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.17:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.17:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.17:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.17:rc5:*:*:*:*:*:*

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