XSS in Discourse Discourse-Encrypt

CVE-2023-43657

discourse-encrypt is a plugin that provides a secure communication channel through Discourse. Improper escaping of encrypted topic titles could lead to a cross site scripting (XSS) issue when a site has content security policy (CSP) headers disabled. Having CSP disabled is a non-default configuration, and having it disabled with discourse-encrypt installed will result in a warning in the Discourse admin dashboard. This has been fixed in commit `9c75810af9` which is included in the latest version of the discourse-encrypt plugin. Users are advised to upgrade. Users unable to upgrade should ensure that CSP headers are enabled and properly configured.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.006 (46.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 46.2% 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-2023-43657: held from 0.005 to 0.006.

EPSS over last 30 days · oldest: 0.005 · newest: 0.006 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2023-43657?
CVE-2023-43657 is a high-severity vulnerability in Discourse Discourse-Encrypt, classified under Cross-site Scripting. CVSS score: 7.2/10. Published 2023-09-28.
How severe is CVE-2023-43657?
High severity. CVSS v3 base score is 7.2 out of 10.