CVEvulnerability

CVE-2026-33393

4.3 MEDIUM Published 2026-03-19 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-03-19
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
4.3 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Weaknesses
CWE-284

Description

Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, the `allowed_spam_host_domains` check used `String#end_with?` without domain boundary validation, allowing domains like `attacker-example.com` to bypass spam protection when `example.com` was allowlisted. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 require exact match or proper subdomain match (preceded by `.`) to prevent suffix-based bypass of `newuser_spam_host_threshold`. No known workarounds are available.

Affected configurations

• discourse discourse (>= 2026.1.0 < 2026.1.2) • discourse discourse (>= 2026.2.0 < 2026.2.1) • discourse discourse 2026.3.0

Related

Weakness · CWE (1)

  • CWE-284 Improper Access Control weakness

References