CVE-2026-47264

Discourse: Don't leak restricted tag group names via tag info

MEDIUM
5.3
CVSS Score
Published: June 12, 2026 at 08:26 PM UTC
Updated: June 17, 2026 at 09:18 PM UTC
1 product affected across 1 vendorDiscourse

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

Discourse is an open-source discussion platform. From versions 2026.1.0-latest to before 2026.1.4, 2026.3.0-latest to before 2026.3.1, and 2026.4.0-latest to before 2026.4.1, DetailedTagSerializer#tag_group_names returned every tag group a tag belonged to without filtering against the requesting user's visibility. With SiteSetting.tags_listed_by_group enabled, anonymous and unprivileged users hitting TagsController#info (which is exempt from requires_login) could read the names of tag groups restricted to specific user groups or non-visible categories. This issue has been patched in versions 2026.1.4, 2026.3.1, 2026.4.1, and 2026.5.0-latest.1.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 2026.1.0v < 2026.1.4v < 2026.3.1v < 2026.4.12026.1.0 ≤ v < 2026.1.42026.3.0 ≤ v < 2026.3.12026.4.0 ≤ v < 2026.4.12026.5.0
Affected range stops below 2026.1.0, so it looks safe — our inference, not a vendor statement
Affected range stops below 2026.1.4, so it looks safe — our inference, not a vendor statement
Affected range stops below 2026.3.1, so it looks safe — our inference, not a vendor statement
Affected range stops below 2026.4.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (1)

x_refsource_CONFIRMThird Party Advisory
Source: cverecord
https://github.com/discourse/discourse/security/advisories/GHSA-4q5q-6hh6-53x2

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-200

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