What is CVE-2018-6378?

CVE-2018-6378 is a medium-severity vulnerability in Joomla Joomla\!, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2018-05-22.

How severe is CVE-2018-6378?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Joomla Joomla\!

CVE-2018-6378

In Joomla! Core before 3.8.8, inadequate filtering of file and folder names leads to various XSS attack vectors in the media manager.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2018-05-22 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.014 (71.1th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 71st percentile — 71.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: -0.000

Affected products

Joomla Joomla\!

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

developer.joomla.org/security-centre/737-20180509-core-xss-vulnerability-in-the… (Vendor Advisory)
www.securityfocus.com/bid/104268 (VDB Entry, Third Party Advisory, vdb-entry)
www.securitytracker.com/id/1040966 (VDB Entry, Third Party Advisory, vdb-entry)

Frequently asked questions

What is CVE-2018-6378?: CVE-2018-6378 is a medium-severity vulnerability in Joomla Joomla\!, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2018-05-22.
How severe is CVE-2018-6378?: Medium severity. CVSS v3 base score is 6.1 out of 10.