How severe is CVE-2021-37748?

CVE-2021-37748 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-2021-37748 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-37748?

CVE-2021-37748 affects Grandstream Ht801 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-37748?

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-2021-37748 published?

CVE-2021-37748 was published on 2021-10-28 and last updated on 2026-06-17.

CVE-2021-37748

CVE-2021-37748 is a high-severity vulnerability in Grandstream Ht801 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-787.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 7% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Grandstream Ht801 Firmware
Published: 2021-10-28
Last modified: 2026-06-17

Description

Multiple buffer overflows in the limited configuration shell (/sbin/gs_config) on Grandstream HT801 devices before 1.0.29 allow remote authenticated users to execute arbitrary code as root via a crafted manage_if setting, thus bypassing the intended restrictions of this shell and taking full control of the device. There are default weak credentials that can be used to authenticate.

Frequently asked questions

What is CVE-2021-37748?: Multiple buffer overflows in the limited configuration shell (/sbin/gs_config) on Grandstream HT801 devices before 1.0.29 allow remote authenticated users to execute arbitrary code as root via a crafted manage_if setting, thus bypassing the intended restrictions of this shell and taking full control of the device. There are default weak credentials that can be used to authenticate.
How severe is CVE-2021-37748?: CVE-2021-37748 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-2021-37748 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-37748?: CVE-2021-37748 affects Grandstream Ht801 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-37748?: 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-2021-37748 published?: CVE-2021-37748 was published on 2021-10-28 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:grandstream:ht801_firmware:*:*:*:*:*:*:*:*

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