XSS in Discourse

CVE-2025-58054

Discourse is an open-source community discussion platform. Versions 3.5.0 and below are vulnerable to XSS attacks through parsing and rendering of chat channel titles and chat thread titles via the quote message functionality when using the rich text editor. This issue is fixed in version 3.5.1.

EPSS: 0.002 (8.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 3.5 (Low). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-58054?
CVE-2025-58054 is a low-severity vulnerability in Discourse, classified under Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS). CVSS score: 3.5/10. Published 2025-10-01.
How severe is CVE-2025-58054?
Low severity. CVSS v3 base score is 3.5 out of 10.
Is CVE-2025-58054 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.