CVE-2026-26973— Discourse doesn't scope reviewable notes to user-visible reviewables
Get alerts for future matching vulnerabilitiesLog in to subscribe
I. Basic Information for CVE-2026-26973
Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗ Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.
Vulnerability Title
Discourse doesn't scope reviewable notes to user-visible reviewables
Source: NVD (National Vulnerability Database)
Vulnerability Description
Discourse is an open source discussion platform. Versions prior to 2025.12.2, 2026.1.1, and 2026.2.0 have an IDOR (Insecure Direct Object Reference) in `ReviewableNotesController`. When `enable_category_group_moderation` is enabled, a user belonging to a category moderation group can create or delete their own notes on **any** reviewable in the system, including reviewables in categories they do not moderate. The controller used an unscoped `Reviewable.find` and the `ensure_can_see` guard only checked whether the user could access the review queue in general, not whether they could access the specific reviewable. Only instances with `enable_category_group_moderation` enabled are affected. Staff users (admins/moderators) are not impacted as they already have access to all reviewables. The issue is patched in versions 2025.12.2, 2026.1.1, and 2026.2.0 by scoping the reviewable lookup through `Reviewable.viewable_by(current_user)`. As a workaround, disable the `enable_category_group_moderation` site setting. This removes the attack surface as only staff users will have access to the review queue.
Source: NVD (National Vulnerability Database)
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Source: NVD (National Vulnerability Database)
Vulnerability Type
授权机制不正确
Source: NVD (National Vulnerability Database)
Vulnerability Title
Discourse 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Discourse是Discourse开源的一套开源的社区讨论平台。该平台包括社区、电子邮件和聊天室等功能。 Discourse 2025.12.2之前版本、2026.1.1之前版本和2026.2.0之前版本存在安全漏洞，该漏洞源于ReviewableNotesController中存在不安全的直接对象引用，可能导致用户越权操作。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
II. Public POCs for CVE-2026-26973
| # | POC Description | Source Link | Shenlong Link |
|---|
AI-Generated POCPremium
No public POC found.
Login to generate AI POCIII. Intelligence Information for CVE-2026-26973
请登录查看更多情报信息。
Same Patch Batch · discourse · 2026-02-26 · 17 CVEs total
| CVE-2026-26265 | 7.5 HIGH | Discourse has IDOR vulnerability in the directory items endpoint |
| CVE-2026-26078 | 7.5 HIGH | Discourse has authentication bypass vulnerability in the Patreon plugin webhook endpoint |
| CVE-2026-26077 | 6.5 MEDIUM | Discourse doesn't ensure webhooks require a token |
| CVE-2026-26207 | 5.4 MEDIUM | DIscourse's discourse-policy plugin lacks post access check |
| CVE-2026-28227 | Discourse Vulnerable to Unauthorized Topic Creation in Staff-Only Categories via Topic Tim | |
| CVE-2026-28219 | Privilege Escalation via Mass Assignment Allows Regular Users to Set Topics as Global Bann | |
| CVE-2026-28218 | Discourse's Fail-Open Access Control in Data Explorer Plugin Allows Unauthorized SQL Query | |
| CVE-2026-27154 | Discourse has XSS when editing a malicious post | |
| CVE-2026-27153 | Discourse doesn't prevent moderators from exporting user Chat DMs | |
| CVE-2026-27152 | DIscourse has DM communication-preference bypass when adding members | |
| CVE-2026-27162 | DIscourse doesn't prevent whispers to leak in excerpts | |
| CVE-2026-27151 | Discourse doesn't validate destination topic when moving posts | |
| CVE-2026-27150 | Discourse doesn't ensure guardian check when creating QueryGroupBookmark | |
| CVE-2026-27149 | Discourse has SQL injection in PM tag filtering | |
| CVE-2026-27021 | Discourse: Poll voters endpoint lacked post visibility checks | |
| CVE-2026-26979 | Discourse: TL4 users are able to change status of restricted topics |
IV. Related Vulnerabilities
Same product: discourse
- CVE-2026-34947
Discourse: Staged user custom fields are exposed on public i - CVE-2026-27481
Discourse: Hidden tag visibility bypass on tag routes - CVE-2026-33415
Discourse: Improper Access Control in discourse-ai Allows Un - CVE-2026-33300
Discourse: Hidden group names and access metadata are expose - CVE-2026-33185
Discourse: Group SMTP test endpoint susceptible to SSRF
Same vendor: discourse
- CVE-2026-34947
Discourse: Staged user custom fields are exposed on public i - CVE-2026-27481
Discourse: Hidden tag visibility bypass on tag routes - CVE-2026-33415
Discourse: Improper Access Control in discourse-ai Allows Un - CVE-2026-33300
Discourse: Hidden group names and access metadata are expose - CVE-2026-33185
Discourse: Group SMTP test endpoint susceptible to SSRF
Same weakness: CWE-863
- CVE-2026-42571
Privilege Escalation Attack affecting Pelican Web UI - CVE-2025-15633
HCL BigFix WebUI is affected by an improper authorization vu - CVE-2026-42296
Argo Workflows has incomplete fix for CVE-2026-31892: hostNe - CVE-2025-66170
Apache CloudStack: Any user can list backups that they shoul - CVE-2026-41903
FreeScout IDOR Vulnerability: PERM_EDIT_USERS allows modifyi
V. Comments for CVE-2026-26973
No comments yet