Is CVE-2023-53921 in the CISA KEV catalog?

No. CVE-2023-53921 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2023-53921?

CVE-2023-53921 has a CVSS v3 base score of 9.8 (CRITICAL).

What is the EPSS score for CVE-2023-53921?

CVE-2023-53921 has an EPSS score of 0.81% (52th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2023-53921

CRITICAL

9.8

CVSS v3

NVD

Description

SitemagicCMS 4.4.3 contains a remote code execution vulnerability that allows attackers to upload malicious PHP files to the files/images directory. Attackers can upload a .phar file with system command execution payload to compromise the web application and execute arbitrary system commands.

CWE-434Unrestricted File Upload

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploit Intelligence

0.81%probability of exploitation in 30 days

52ndpercentile

Moderate risk: more likely to be exploited than 52% of all known CVEs.

References

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-12-31.