Is CVE-2023-4739 actively exploited?

No active exploitation of CVE-2023-4739 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2023-4739 be exploited remotely?

Yes. CVE-2023-4739 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2023-4739?

CVE-2023-4739 has a CVSS score of 9.8 (CRITICAL).

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CRITICAL

CVE-2023-4739

CWE-434Published: September 3, 2023· Updated: Jun 17, 2026

9.8

CVSS v3.1

Official 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.

NVD Source

Risk Analysis

Byzoro Smart S85F Management Platform contains a critical unrestricted file upload vulnerability in the updateos.php file. Remote attackers can exploit this to upload arbitrary files, earning a CVSS score of 9.8.

Public exploit details have been disclosed, but the flaw is not in the KEV database. It is remotely exploitable with low complexity.

Recommended Action

Update the device firmware to the latest version. Restrict access to the management interface to trusted network segments.

Generated by the CTIWATCH analysis pipeline from this CVE's metadata (CVSS, EPSS, KEV status, exploit intelligence). Verify against vendor advisories before acting.

Technical Analysis

CVE-2023-4739 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.