CVE Tools
Sign in

CVE-2026-72722

Discourse: Duplicate lookup reveals restricted topic titles through canonicalized URLs

Published: Aug 10, 2026Updated: Aug 13, 2026 Sources: CVE List NVDCWE-862
4.3MEDIUM
NVD MITRE
EPSS Score
0.3%
Top 75.3%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
No Fix Available
Self-Check
OpenVAS

Description

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, TopicLink.extract_from, TopicLink.ensure_entry_for, and TopicLink.duplicate_lookup do not consistently enforce Guardian.can_see? checks when processing internal links. An authenticated user can submit links to restricted topics, private messages, or hidden posts and receive canonicalized slugs or titles in the composer_messages duplicate_lookup response even though the targets are not visible to that user. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:LI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:LConfidentiality
Low
I:NIntegrity
None
A:NAvailability
None
Open in CVSS calculator →

Weaknesses

CWE-862

Affected Products

discourse
commercial·USaka discourse.org
discourse
Web & CMS Plugins

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.
Is your org exposed to CVE-2026-72722?We can run the check for you — a free external exposure review, no install. Check my exposure

Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

2 techniques
Initial Access
View detailed technique mapping

References

https://github.com/discourse/discourse/commit/45abd925e46e8be40d2d047bced26628f26e4e31
github.com
https://github.com/discourse/discourse/commit/7d7ce546ac86e24a6512b321ace69fc52fe37bf4
github.com
https://github.com/discourse/discourse/commit/836a251d54a1004fb1c463a7d299b933b176191f
github.com
and 6 more references View all →

Unlock Complete Vulnerability Intelligence

Get the full picture for CVE-2026-72722 and every CVE in our database. Create a free account — no credit card required.

Create Free Account
Plain-language analysis
Impact assessment and exploitation scenario in plain English
Attack graph visualization
Interactive attack path and kill chain mapping
Exploit details & PoC links
ExploitDB, Metasploit, GitHub PoCs with direct links
Nuclei scanner templates
Ready-to-use vulnerability scanner templates
Full remediation guide
Patch instructions, workarounds, and compliance impact
Interactive AI chat
Ask questions about this vulnerability in natural language
Related vulnerabilities
Semantically similar CVEs and attack patterns
REST API & MCP access
Integrate vulnerability data into your workflows