CVE-2023-53979

Name: CVE-2023-53979
Creator: NVD / NIST
Published: 2025-12-22T22:16:03.54+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.6/10EPSS 0.70%

Last modified Jun 17, 2026

CVE-2023-53979 is a high-severity vulnerability rated 8.6/10 on the CVSS scale. MyBB 1.8.32 contains a chained vulnerability that allows authenticated administrators to bypass avatar upload restrictions and execute arbitrary code. Attackers can modify upload path settings, upload a malicious PHP-embedded image file, and execute commands through the language configuration editing interface.. EPSS estimates a 0.70% chance of exploitation in the next 30 days.

Description

MyBB 1.8.32 contains a chained vulnerability that allows authenticated administrators to bypass avatar upload restrictions and execute arbitrary code. Attackers can modify upload path settings, upload a malicious PHP-embedded image file, and execute commands through the language configuration editing interface.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/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

0.70%

48.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-22

Affected Software

Vendor	Product	Versions
Mybb	Mybb	1.8.32

References

https://fdlucifer.github.io/2023/01/17/mybb1-8-32-LFI-RCE/Exploit, Third Party Advisory
https://mybb.com/Product
https://www.exploit-db.com/exploits/51213Exploit
https://www.vulncheck.com/advisories/mybb-authenticated-remote-code-execution-via-chained-vulnerabilitiesExploit, Third Party Advisory
https://www.cve.org/CVERecord?id=CVE-2022-45867

Timeline

Published: Dec 22, 2025
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-53979?

How severe is CVE-2023-53979?

CVE-2023-53979 has a CVSS score of 8.6/10 (HIGH severity). The EPSS model estimates a 0.70% probability of exploitation in the next 30 days.

How do I fix CVE-2023-53979?

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-2023-53979?

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

Scan your code now

Source: NVD / NIST