How severe is CVE-2021-42851?

CVE-2021-42851 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2021-42851 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42851?

CVE-2021-42851 primarily affects Lenovo A1 Firmware. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-42851?

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

When was CVE-2021-42851 published?

CVE-2021-42851 was published on 2022-05-18 and last updated on 2026-06-17.

CVE-2021-42851

CVE-2021-42851 is a medium-severity vulnerability in Lenovo A1 Firmware with a CVSS 3.x base score of 6.3. 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-862.

Key facts

Severity: Medium (CVSS 3.x base score 6.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-862
Affected product: Lenovo A1 Firmware
Published: 2022-05-18
Last modified: 2026-06-17

Description

A vulnerability was reported in some Lenovo Personal Cloud Storage devices that could allow an unauthenticated user to create a standard user account.

Frequently asked questions

What is CVE-2021-42851?: A vulnerability was reported in some Lenovo Personal Cloud Storage devices that could allow an unauthenticated user to create a standard user account.
How severe is CVE-2021-42851?: CVE-2021-42851 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2021-42851 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42851?: CVE-2021-42851 primarily affects Lenovo A1 Firmware. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-42851?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-42851 published?: CVE-2021-42851 was published on 2022-05-18 and last updated on 2026-06-17.

References

https://iknow.lenovo.com.cn/detail/dc_200017.html

Affected products (5)

cpe:2.3:o:lenovo:a1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:t1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:x1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:t2_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:t2pro_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Lenovo A1 Firmware

CVE-2021-42850 — High (CVSS 8.8): A weak default administrator password for the web interface and serial port was reported in some Lenovo Personal Cloud…
CVE-2021-42852 — High (CVSS 8.0): A command injection vulnerability was reported in some Lenovo Personal Cloud Storage devices that could allow an…
CVE-2021-42849 — Medium (CVSS 6.8): A weak default password for the serial port was reported in some Lenovo Personal Cloud Storage devices that could allow…
CVE-2021-42848 — Medium (CVSS 4.3): An information disclosure vulnerability was reported in some Lenovo Personal Cloud Storage devices that could allow an…

All CVEs affecting Lenovo A1 Firmware →

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