CVE-2023-47119

Table of contents CVE-2023-47119 Detailed analysis POC Escalation ? LAB Setup CVE-2023-47119 A POC for CVE-2023-47119 which is a vulnerability affecting Discourse versions prior to version 3.1.3 of the stable branch and version 3.2.0.beta3 of the beta and tests-passed branches. Some links can...

Discourse <=2026.2.0 - Hidden Post Revision Disclosure via revert_to Authorization Bypass

Discourse versions before 2026.1.2, 2026.2.1, and 2026.3.0-latest.1 contain an authorization bypass in PostsControllerdisplaypost. The controller calls post.reverttoparams:version directly whenever a version query parameter is present, without checking whether the corresponding PostRevision is...

Discourse - Private Group Membership Inference via exclude_groups

Discourse 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contains an information disclosure caused by unauthenticated users observing directory results changes with the excludegroups parameter, letting attackers determine private group membership, exploit requires public access to user directory. id:...

Discourse < 2026.1.2/2026.2.1/2026.3.0-latest.1 - Unauthenticated Private User Action Disclosure

Discourse 2026.1.2/2026.2.1/2026.3.0-latest.1 contains an information disclosure vulnerability caused by lack of visibility checks in a user action API endpoint, letting unauthorized users access post titles and excerpts, exploit requires no special privileges. id: CVE-2026-27934 info: name:...

Discourse - Private User Field Disclosure via Directory Items IDOR

Discourse prior to 2025.12.2, 2026.1.1, and 2026.2.0 contains an IDOR vulnerability caused by lack of authorization checks on userfieldids parameter in DirectoryItemsControllerindex, letting any user retrieve private user field values, exploit requires no authentication. id: CVE-2026-26265 info:...

Discourse - Unauthenticated Mailpace Webhook Bounce-Score Forgery

Discourse's WebhooksController contains a missing-authentication flaw caused by accepting requests to provider webhook endpoints including /webhooks/mailpace, SendGrid, Mailjet, Mandrill, Postmark, and SparkPost without validating a token when none is configured, which is the default state, letti...

Discourse OAuth Social Login - Cross-site Scripting

Discourse versions prior to 3.5.0.beta6 contain a stored Cross-Site Scripting XSS vulnerability in the OAuth/social login functionality. The vulnerability is caused by lack of proper content security policy enforcement when processing social login failures,allowing remote attackers to inject and...

CVE-2024-52794-Discourse-Stored-XSS

CVE-2024-52794 – Stored Cross-Site Scripting XSS in Discourse Summary I discovered a stored cross-site scripting XSS vulnerability in Discourse, an open-source forum platform. The vulnerability allows an attacker to execute arbitrary JavaScript in the victim’s browser by injecting a malicious...

discourse-CVE-2023-45806

yksivaihde-CVE-2023-45806 CVE: https://github.com/discourse/discourse/security/advisories/GHSA-hcgf-hg2g-mw78 Patch: https://github.com/discourse/discourse/commit/7d484864fe91ff79c478f57e7ddb1235d701921e usage: fixquoteattribution"Username|", , where "Username|" is the unique search string within...

CVE-2021-3138

..| Discourse 2.7.0 - CVE-2021-3138 |.. Description : Rate limit Bypass which leads to 2FA Bypass Tested Version : 2.7.0 Attack Type: Remote Impact : 2FA Bypass Vendor of Product : https://www.discourse.org Additional Information : Discourse is discussion platform built for the next decade of the...

Discourse Backup File Disclosure Via Default Nginx Configuration

Discourse is an open source platform for community discussion. This vulnerability only impacts Discourse instances configured to use FileStore--LocalStore which means uploads and backups are stored locally on disk. If an attacker knows the name of the Discourse backup file, the attacker can trick...

CVE-2017-20290

Discourse 1.9.0.beta2 before 1.9.0.beta13 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject scripts through the email parameter of /email/unsubscribed. Attackers can craft GET requests with SVG onload payloads, which unsubscribed.html.erb...

CVE-2017-20290

Discourse 1.9.0.beta2 before 1.9.0.beta13 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject scripts through the email parameter of /email/unsubscribed. Attackers can craft GET requests with SVG onload payloads, which unsubscribed.html.erb...

EUVD-2017-19027

Discourse 1.9.0.beta2 before 1.9.0.beta13 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject scripts through the email parameter of /email/unsubscribed. Attackers can craft GET requests with SVG onload payloads, which unsubscribed.html.erb...

CVE-2017-20290 Discourse < 1.9.0.beta13 Reflected XSS via /email/unsubscribed

Discourse 1.9.0.beta2 before 1.9.0.beta13 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject scripts through the email parameter of /email/unsubscribed. Attackers can craft GET requests with SVG onload payloads, which unsubscribed.html.erb...

CVE-2017-20290

Discourse versions 1.9.0.beta2 before 1.9.0.beta13 are vulnerable to a reflected cross-site scripting (XSS) vulnerability. The issue exists because the email parameter of the /email/unsubscribed endpoint is rendered unescaped via html_safe in the unsubscribed.html.erb file. Unauthenticated attack...

VulnCheck KEV: CVE-2017-20290

Discourse 1.9.0.beta2 before 1.9.0.beta13 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject scripts through the email parameter of /email/unsubscribed. Attackers can craft GET requests with SVG onload payloads, which unsubscribed.html.erb...

CVE-2017-20290: Improper Neutralization of Input During Web Page Generation

Discourse 1.9.0.beta2 before 1.9.0.beta13 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject scripts through the email parameter of /email/unsubscribed. Attackers can craft GET requests with SVG onload payloads, which unsubscribed.html.erb...

PT-2026-121377

Discourse 1.9.0.beta2 before 1.9.0.beta13 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject scripts through the email parameter of /email/unsubscribed. Attackers can craft GET requests with SVG onload payloads, which unsubscribed.html.erb...

Discourse cross-site scripting vulnerability

Versions 1.9.0.beta2 through 1.9.0.beta13 of Discourse contain a cross-site scripting vulnerability. This arises from the lack of validation on the /email/unsubscribed email parameter; the unsubscribed.html.erb file uses htmlsafe without proper escaping. As a result, it may be exploited for...