XSS in WordPress

CVE-2020-4049

In affected versions of WordPress, when uploading themes, the name of the theme folder can be crafted in a way that could lead to JavaScript execution in /wp-admin on the themes page. This does require an admin to upload the theme, and is low severity self-XSS. This has been patched in version 5.4.2, along with all the previously affected versions via a minor release (5.3.4, 5.2.7, 5.1.6, 5.0.10, 4.9.15, 4.8.14, 4.7.18, 4.6.19, 4.5.22, 4.4.23, 4.3.24, 4.2.28, 4.1.31, 4.0.31, 3.9.32, 3.8.34, 3.7.34).

Published · last modified .

CVSS v3 metric

CVSS v3 base score 2.4 (Low). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.025 (84.3th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 84th percentile — 84.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2020-4049: held from 0.025 to 0.025.

EPSS over last 30 days · oldest: 0.025 · newest: 0.025 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2020-4049?
CVE-2020-4049 is a low-severity vulnerability in WordPress, classified under Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS). CVSS score: 2.4/10. Published 2020-06-12.
How severe is CVE-2020-4049?
Low severity. CVSS v3 base score is 2.4 out of 10.
Is CVE-2020-4049 known to be exploited?
5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.