CVE-2026-49256

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/discourse/discourse/releases/tag/v2026.1.5	Release Notes Patch
https://github.com/discourse/discourse/releases/tag/v2026.4.2	Release Notes
https://github.com/discourse/discourse/releases/tag/v2026.5.1	Release Notes
https://github.com/discourse/discourse/releases/tag/v2026.6.0	Release Notes
https://github.com/discourse/discourse/security/advisories/GHSA-mwp7-572g-6qpx	Vendor Advisory Mitigation

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse:2026.6.0::::latest:::

History

No history.

Information

Published : 2026-07-09 22:17

Updated : 2026-07-14 20:40

NVD link : CVE-2026-49256

Mitre link : CVE-2026-49256

CVE.ORG link : CVE-2026-49256

JSON object : View

Products Affected

discourse

discourse

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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