XSS in Xenforo

CVE-2021-43032

In XenForo through 2.2.7, a threat actor with access to the admin panel can create a new Advertisement via the Advertising function, and save an XSS payload in the body of the HTML document. This payload will execute globally on the client side.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.009 (58.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 58.4% 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-2021-43032: held from 0.009 to 0.009.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-43032?
CVE-2021-43032 is a medium-severity vulnerability in Xenforo, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2021-11-03.
How severe is CVE-2021-43032?
Medium severity. CVSS v3 base score is 4.8 out of 10.
Is CVE-2021-43032 known to be exploited?
3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.