How severe is CVE-2021-39434?

CVE-2021-39434 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 high, integrity none, and availability none.

Is CVE-2021-39434 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-39434?

CVE-2021-39434 primarily affects Zkteco Zktime. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-39434?

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-2021-39434 published?

CVE-2021-39434 was published on 2022-12-06 and last updated on 2026-06-17.

CVE-2021-39434

CVE-2021-39434 is a high-severity vulnerability in Zkteco Zktime 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-521.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-521
Affected product: Zkteco Zktime
Published: 2022-12-06
Last modified: 2026-06-17

Description

A default username and password for an administrator account was discovered in ZKTeco ZKTime 10.0 through 11.1.0, builds 20180901, 20190510.1, 20200309.3, 20200930, 20201231, and 20210220.

Frequently asked questions

What is CVE-2021-39434?: A default username and password for an administrator account was discovered in ZKTeco ZKTime 10.0 through 11.1.0, builds 20180901, 20190510.1, 20200309.3, 20200930, 20201231, and 20210220.
How severe is CVE-2021-39434?: CVE-2021-39434 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 high, integrity none, and availability none.
Is CVE-2021-39434 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-39434?: CVE-2021-39434 primarily affects Zkteco Zktime. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-39434?: 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-2021-39434 published?: CVE-2021-39434 was published on 2022-12-06 and last updated on 2026-06-17.

References

https://www.cnvd.org.cn/flaw/show/CNVD-2018-26041

Affected products (8)

cpe:2.3:a:zkteco:zktime:*:*:*:*:*:*:*:*
cpe:2.3:a:zkteco:zktime:11.1.0:-:*:*:*:*:*:*
cpe:2.3:a:zkteco:zktime:11.1.0:20180901:*:*:*:*:*:*
cpe:2.3:a:zkteco:zktime:11.1.0:20190510.1:*:*:*:*:*:*
cpe:2.3:a:zkteco:zktime:11.1.0:20200309.3:*:*:*:*:*:*
cpe:2.3:a:zkteco:zktime:11.1.0:20200930:*:*:*:*:*:*
cpe:2.3:a:zkteco:zktime:11.1.0:20201231:*:*:*:*:*:*
cpe:2.3:a:zkteco:zktime:11.1.0:20210220:*:*:*:*:*:*

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