What is CVE-2021-25968?

CVE-2021-25968 is a medium-severity vulnerability in Alkacon Opencms, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2021-10-19.

How severe is CVE-2021-25968?

Medium severity. CVSS v3 base score is 5.4 out of 10.

XSS in Alkacon Opencms

CVE-2021-25968

In “OpenCMS”, versions 10.5.0 to 11.0.2 are affected by a stored XSS vulnerability that allows low privileged application users to store malicious scripts in the Sitemap functionality. These scripts are executed in a victim’s browser when they open the page containing the vulnerable field.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2021-10-19 · last modified 2026-06-17.

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.

EPSS exploit prediction

EPSS: 0.005 (41.5th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 41.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Alkacon Opencms
Org.opencms Opencms-Core — versions 10.5.0, unspecified

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

www.whitesourcesoftware.com/vulnerability-database/CVE-2021-25968 (Broken Link)
github.com/alkacon/mercury-template/commit/800945f5d02346c633c7aef9f5d596d7dedc… (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2021-25968?: CVE-2021-25968 is a medium-severity vulnerability in Alkacon Opencms, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2021-10-19.
How severe is CVE-2021-25968?: Medium severity. CVSS v3 base score is 5.4 out of 10.