XSS in Mybb

CVE-2021-41866

MyBB before 1.8.28 allows stored XSS because the displayed Template Name value in the Admin CP's theme management is not escaped properly.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.005 (38.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

Affected products

Mybb
N/a — versions n/a

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

cve@mitre.org (Third Party Advisory, x_refsource_MISC)
cve@mitre.org (x_refsource_CONFIRM, Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2021-41866?: CVE-2021-41866 is a medium-severity vulnerability in Mybb, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2021-10-26.
How severe is CVE-2021-41866?: Medium severity. CVSS v3 base score is 5.4 out of 10.