What is CVE-2026-21431?

CVE-2026-21431 is a medium-severity vulnerability in Emlog, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-01-02.

How severe is CVE-2026-21431?

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

XSS in Emlog

CVE-2026-21431

Emlog is an open source website building system. Version 2.5.23 has a stored cross-site scripting vulnerability in the `Resource media library ` function while publishing an article. As of time of publication, no known patched versions are available.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.002 (5.8th 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

Emlog — versions 2.5.23, = 2.5.23

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)

Frequently asked questions

What is CVE-2026-21431?: CVE-2026-21431 is a medium-severity vulnerability in Emlog, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-01-02.
How severe is CVE-2026-21431?: Medium severity. CVSS v3 base score is 5.4 out of 10.