How severe is CVE-2020-7869?

CVE-2020-7869 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-7869 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-7869?

CVE-2020-7869 affects Mastersoft Zook. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-7869?

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-2020-7869 published?

CVE-2020-7869 was published on 2021-06-29 and last updated on 2026-06-17.

CVE-2020-7869

CVE-2020-7869 is a critical-severity vulnerability in Mastersoft Zook with a CVSS 3.x base score of 9.0. 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-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.0)
CVSS v2: 9.0
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mastersoft Zook
Published: 2021-06-29
Last modified: 2026-06-17

Description

An improper input validation vulnerability of ZOOK software (remote administration tool) could allow a remote attacker to create arbitrary file. The ZOOK viewer has the "Tight file CMD" function to create file. An attacker could create and execute arbitrary file in the ZOOK agent program using "Tight file CMD" without authority.

Frequently asked questions

What is CVE-2020-7869?: An improper input validation vulnerability of ZOOK software (remote administration tool) could allow a remote attacker to create arbitrary file. The ZOOK viewer has the "Tight file CMD" function to create file. An attacker could create and execute arbitrary file in the ZOOK agent program using "Tight file CMD" without authority.
How severe is CVE-2020-7869?: CVE-2020-7869 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-7869 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-7869?: CVE-2020-7869 affects Mastersoft Zook. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-7869?: 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-2020-7869 published?: CVE-2020-7869 was published on 2021-06-29 and last updated on 2026-06-17.

References

https://www.boho.or.kr/krcert/secNoticeView.do?bulletin_writing_sequence=36090

Affected products (1)

cpe:2.3:a:mastersoft:zook:2.0.4.6:*:*:*:*:*:*:*

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