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CVE-2026-49256

Discourse: Hidden tag names leaked via category serializers

Published: Jul 9, 2026Updated: Jul 14, 2026 Sources: CVE List NVDCWE-200
7.5HIGH
NVD MITRE
EPSS Score
0.4%
Top 70.0%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, restricted tag and tag-group names attached to publicly readable categories as allowed_tags, allowed_tag_groups, or required tag groups could leak to anonymous and unauthorized users through category and group endpoints. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:NIntegrity
None
A:NAvailability
None
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Weaknesses

CWE-200

Affected Products

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

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Collection
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References

https://github.com/discourse/discourse/security/advisories/GHSA-mwp7-572g-6qpx
github.com
https://github.com/discourse/discourse/releases/tag/v2026.1.5
github.com
https://github.com/discourse/discourse/releases/tag/v2026.4.2
github.com
and 2 more references View all →

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