Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, several webhook endpoints (SendGrid, Mailjet, Mandrill, Postmark, SparkPost) in the `WebhooksController` accepted requests without a valid authentication token when no token was configured. This allowed unauthenticated attackers to forge webhook payloads and artificially inflate user bounce scores, potentially causing legitimate user emails to be disabled. The Mailpace endpoint had no token validation at all. Starting in versions 2025.12.2, 2026.1.1, and 2026.2.0, all webhook endpoints reject requests with a 406 response when no authentication token is configured. As a workaround, ensure that webhook authentication tokens are configured for all email provider integrations in site settings (e.g., `sendgrid_verification_key`, `mailjet_webhook_token`, `postmark_webhook_token`, `sparkpost_webhook_token`). There's no current workaround for mailpace before getting this fix.
References
| Link | Resource |
|---|---|
| https://github.com/discourse/discourse/security/advisories/GHSA-j67c-53j2-4hfw | Vendor Advisory |
Configurations
Configuration 1 (hide)
|
History
02 Mar 2026, 21:53
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://github.com/discourse/discourse/security/advisories/GHSA-j67c-53j2-4hfw - Vendor Advisory | |
| CPE | cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:* cpe:2.3:a:discourse:discourse:2026.2.0:*:*:*:latest:*:*:* |
|
| First Time |
Discourse
Discourse discourse |
|
| Summary |
|
26 Feb 2026, 15:17
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-02-26 15:17
Updated : 2026-03-02 21:53
NVD link : CVE-2026-26077
Mitre link : CVE-2026-26077
CVE.ORG link : CVE-2026-26077
JSON object : View
Products Affected
discourse
- discourse
CWE
CWE-287
Improper Authentication
