How severe is CVE-2020-5756?

CVE-2020-5756 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-5756 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5756?

CVE-2020-5756 affects Grandstream Gwn7000 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-5756?

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-2020-5756 published?

CVE-2020-5756 was published on 2020-07-17 and last updated on 2026-06-17.

CVE-2020-5756

CVE-2020-5756 is a high-severity vulnerability in Grandstream Gwn7000 Firmware with a CVSS 3.x base score of 8.8. 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-78.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 2% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Grandstream Gwn7000 Firmware
Published: 2020-07-17
Last modified: 2026-06-17

Description

Grandstream GWN7000 firmware version 1.0.9.4 and below allows authenticated remote users to modify the system's crontab via undocumented API. An attacker can use this functionality to execute arbitrary OS commands on the router.

Frequently asked questions

What is CVE-2020-5756?: Grandstream GWN7000 firmware version 1.0.9.4 and below allows authenticated remote users to modify the system's crontab via undocumented API. An attacker can use this functionality to execute arbitrary OS commands on the router.
How severe is CVE-2020-5756?: CVE-2020-5756 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-5756 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5756?: CVE-2020-5756 affects Grandstream Gwn7000 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-5756?: 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-2020-5756 published?: CVE-2020-5756 was published on 2020-07-17 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:grandstream:gwn7000_firmware:*:*:*:*:*:*:*:*

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