CVE-2026-33427

Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, an unauthenticated attacker can cause a legitimate Discourse authorization page to display an attacker-controlled domain, facilitating social engineering attacks against users. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/discourse/discourse/security/advisories/GHSA-9vhg-2mx3-mqfr	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse:2026.3.0::::latest:::

History

24 Mar 2026, 19:46

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
CPE		cpe:2.3:a:discourse:discourse:2026.3.0::::latest::: cpe:2.3:a:discourse:discourse::::::::
References	~~() https://github.com/discourse/discourse/security/advisories/GHSA-9vhg-2mx3-mqfr -~~	() https://github.com/discourse/discourse/security/advisories/GHSA-9vhg-2mx3-mqfr - Vendor Advisory
First Time		Discourse Discourse discourse

21 Mar 2026, 00:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-21 00:16

Updated : 2026-03-24 19:46

NVD link : CVE-2026-33427

Mitre link : CVE-2026-33427

CVE.ORG link : CVE-2026-33427

JSON object : View

Products Affected

discourse

discourse

CWE

CWE-862

Missing Authorization

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