Path Traversal in Mybb
CVE-2023-53979
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.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.008 (55.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 55.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: +0.000
Affected products
- Mybb — versions 1.8.32, MyBB 1.8.32
Weakness classification (CWE)
References
- www.exploit-db.com/exploits/51213 (Exploit, exploit)
- mybb.com/ (Product, product)
- fdlucifer.github.io/2023/01/17/mybb1-8-32-LFI-RCE/ (Exploit, technical-description, Third Party Advisory)
- www.vulncheck.com/advisories/mybb-authenticated-remote-code-execution-via-chain… (Exploit, Third Party Advisory, third-party-advisory)
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2023-53979?
- CVE-2023-53979 is a high-severity vulnerability in Mybb, classified under Path Traversal. CVSS score: 8.8/10. Published 2025-12-22.
- How severe is CVE-2023-53979?
- High severity. CVSS v3 base score is 8.8 out of 10.