Vulnerability · Published Feb 26, 2026 · Assigned by GitHub_M

CVE-2026-27154Discourse has XSS when editing a malicious post

Low 1.3

In plain English

A low-severity cross-site scripting in discourse from discourse. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 7% of all known vulnerabilities).

Severity (CVSS 4.0)1.3Low
Exploit odds (30 days)0.2%top 92.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, a user full name can be evaluated as raw HTML when the following settings are set: `display_name_on_posts` => true; and `prioritize_username_in_ux` => false. Editing a post of a malicious user would trigger an XSS. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.

Affected products (as reported)

VendorProductVersions
discourse discourse < 2025.12.2>= 2026.1.0-latest, < 2026.1.1>= 2026.2.0-latest, < 2026.2.0

Weakness: CWE-79 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U

References