CVE-2020-20979

Name: CVE-2020-20979
Creator: NVD / NIST
Published: 2021-08-12T15:15:07.47+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 1.60%

Last modified Jun 17, 2026

CVE-2020-20979 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. An arbitrary file upload vulnerability in the move_uploaded_file() function of LJCMS v4.3 allows attackers to execute arbitrary code.. EPSS estimates a 1.60% chance of exploitation in the next 30 days.

Description

An arbitrary file upload vulnerability in the move_uploaded_file() function of LJCMS v4.3 allows attackers to execute arbitrary code.

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

1.60%

72.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-434

Affected Software

Vendor	Product	Versions
8cms	Ljcms	4.3.-

References

https://github.com/0xyu/PHP_Learning/issues/2Exploit, Issue Tracking, Third Party Advisory
https://github.com/0xyu/PHP_Learning/issues/2Exploit, Issue Tracking, Third Party Advisory

Timeline

Published: Aug 12, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-20979?

An arbitrary file upload vulnerability in the move_uploaded_file() function of LJCMS v4.3 allows attackers to execute arbitrary code.

How severe is CVE-2020-20979?

CVE-2020-20979 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 1.60% probability of exploitation in the next 30 days.

How do I fix CVE-2020-20979?

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-2020-20979?

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

Scan your code now

Source: NVD / NIST