What is CVE-2025-67723?

CVE-2025-67723 is a medium-severity vulnerability in Discourse, classified under Cross-site Scripting. CVSS score: 4.6/10. Published 2026-01-28.

How severe is CVE-2025-67723?

Medium severity. CVSS v3 base score is 4.6 out of 10.

XSS in Discourse

CVE-2025-67723

Discourse is an open source discussion platform. Versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 have a content-security-policy-mitigated cross-site scriptinv vulnerability on the Discourse Math plugin when using its KaTeX variant. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. As a workaround, the Discourse Math plugin can be disabled, or the Mathjax provider can be used instead of KaTeX.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.002 (9.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.6 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:L.

Affected products

Discourse — versions >= 2026.1.0-latest, < 2026.1.0, >= 2025.12.0-latest, < 2025.12.1, < 3.5.4

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

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

Frequently asked questions

What is CVE-2025-67723?: CVE-2025-67723 is a medium-severity vulnerability in Discourse, classified under Cross-site Scripting. CVSS score: 4.6/10. Published 2026-01-28.
How severe is CVE-2025-67723?: Medium severity. CVSS v3 base score is 4.6 out of 10.