CVE-2021-47734

Name: CVE-2021-47734
Creator: NVD / NIST
Published: 2025-12-23T20:15:45.123+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.6/10EPSS 0.71%

Last modified Jun 17, 2026

CVE-2021-47734 is a high-severity vulnerability rated 8.6/10 on the CVSS scale. CMSimple 5.4 contains an authenticated local file inclusion vulnerability that allows remote attackers to manipulate PHP session files and execute arbitrary code. Attackers can leverage the vulnerability by changing the functions file path and uploading malicious PHP code through session file upload mechanisms.. EPSS estimates a 0.71% chance of exploitation in the next 30 days.

Description

CMSimple 5.4 contains an authenticated local file inclusion vulnerability that allows remote attackers to manipulate PHP session files and execute arbitrary code. Attackers can leverage the vulnerability by changing the functions file path and uploading malicious PHP code through session file upload mechanisms.

Metrics

CVSS 3.1

7.8/10

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

CVSS 4.0

8.6/10

CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.71%

48.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-98

Affected Software

Vendor	Product	Versions
Cmsimple	Cmsimple	5.4

References

https://www.cmsimple.org/en/Product
https://www.exploit-db.com/exploits/50547Exploit
https://www.vulncheck.com/advisories/cmsimple-authenticated-local-file-inclusion-remote-code-executionThird Party Advisory

Timeline

Published: Dec 23, 2025
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-47734?

How severe is CVE-2021-47734?

CVE-2021-47734 has a CVSS score of 8.6/10 (HIGH severity). The EPSS model estimates a 0.71% probability of exploitation in the next 30 days.

How do I fix CVE-2021-47734?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-47734?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST