How severe is CVE-2021-40056?

CVE-2021-40056 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-40056 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-40056?

CVE-2021-40056 primarily affects Huawei Emui. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-40056?

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.

When was CVE-2021-40056 published?

CVE-2021-40056 was published on 2022-03-10 and last updated on 2026-06-17.

CVE-2021-40056

CVE-2021-40056 is a high-severity vulnerability in Huawei Emui with a CVSS 3.x base score of 7.5. 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-120.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Huawei Emui
Published: 2022-03-10
Last modified: 2026-06-17

Description

There is a vulnerability of copying input buffer without checking its size in the video framework. Successful exploitation of this vulnerability may affect availability.

Frequently asked questions

What is CVE-2021-40056?: There is a vulnerability of copying input buffer without checking its size in the video framework. Successful exploitation of this vulnerability may affect availability.
How severe is CVE-2021-40056?: CVE-2021-40056 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-40056 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-40056?: CVE-2021-40056 primarily affects Huawei Emui. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-40056?: 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.
When was CVE-2021-40056 published?: CVE-2021-40056 was published on 2022-03-10 and last updated on 2026-06-17.

References

https://consumer.huawei.com/en/support/bulletin/2022/3/

Affected products (4)

cpe:2.3:o:huawei:emui:10.0.0:*:*:*:*:*:*:*
cpe:2.3:o:huawei:emui:10.1.0:*:*:*:*:*:*:*
cpe:2.3:o:huawei:magic_ui:3.1.0:*:*:*:*:*:*:*
cpe:2.3:o:huawei:magic_ui:3.1.1:*:*:*:*:*:*:*

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