How severe is CVE-2023-4739?

CVE-2023-4739 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2023-4739 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-4739?

CVE-2023-4739 affects Byzoro Smart S85f Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-4739?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-4739 published?

CVE-2023-4739 was published on 2023-09-03 and last updated on 2026-06-17.

CVE-2023-4739

CVE-2023-4739 is a medium-severity vulnerability in Byzoro Smart S85f Firmware with a CVSS 3.x base score of 6.3. 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-434.

Key facts

Severity: Medium (CVSS 3.x base score 6.3)
CVSS v2: 6.5
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Byzoro Smart S85f Firmware
Published: 2023-09-03
Last modified: 2026-06-17

Description

A vulnerability, which was classified as critical, has been found in Byzoro Smart S85F Management Platform up to 20230820. Affected by this issue is some unknown functionality of the file /sysmanage/updateos.php. The manipulation of the argument 1_file_upload leads to unrestricted upload. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-238628. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.

Frequently asked questions

What is CVE-2023-4739?: A vulnerability, which was classified as critical, has been found in Byzoro Smart S85F Management Platform up to 20230820. Affected by this issue is some unknown functionality of the file /sysmanage/updateos.php. The manipulation of the argument 1_file_upload leads to unrestricted upload. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-238628. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.
How severe is CVE-2023-4739?: CVE-2023-4739 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2023-4739 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-4739?: CVE-2023-4739 affects Byzoro Smart S85f Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-4739?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-4739 published?: CVE-2023-4739 was published on 2023-09-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:byzoro:smart_s85f_firmware:*:*:*:*:*:*:*:*

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