How severe is CVE-2023-47304?

CVE-2023-47304 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-47304 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-47304?

CVE-2023-47304 affects Vonage Vdv23 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-47304?

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-2023-47304 published?

CVE-2023-47304 was published on 2023-12-05 and last updated on 2026-06-17.

CVE-2023-47304

CVE-2023-47304 is a high-severity vulnerability in Vonage Vdv23 Firmware with a CVSS 3.x base score of 7.8. 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-287.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 0% (20th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Vonage Vdv23 Firmware
Published: 2023-12-05
Last modified: 2026-06-17

Description

An issue was discovered in Vonage Box Telephone Adapter VDV23 version VDV21-3.2.11-0.5.1, allows local attackers to bypass UART authentication controls and read/write arbitrary values to the memory of the device.

Frequently asked questions

What is CVE-2023-47304?: An issue was discovered in Vonage Box Telephone Adapter VDV23 version VDV21-3.2.11-0.5.1, allows local attackers to bypass UART authentication controls and read/write arbitrary values to the memory of the device.
How severe is CVE-2023-47304?: CVE-2023-47304 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-47304 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-47304?: CVE-2023-47304 affects Vonage Vdv23 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-47304?: 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-2023-47304 published?: CVE-2023-47304 was published on 2023-12-05 and last updated on 2026-06-17.

References

https://trojanhorsey.substack.com/p/cve-2023-47304-unsecured-uart-in

Affected products (1)

cpe:2.3:o:vonage:vdv23_firmware:vdv21-3.2.11-0.5.1:*:*:*:*:*:*:*

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