CVE-2026-49256

MEDIUM

Discourse: Hidden tag names leaked via category serializers

Title source: cna
STIX 2.1

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.

References (5)

Core 5

Scores

CVSS v4 6.3
EPSS 0.0038
EPSS Percentile 30.5%
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-200
Status published
Products (3)
discourse/discourse >= 2026.1.0-latest, < 2026.1.5
discourse/discourse >= 2026.4.0-latest, < 2026.4.2
discourse/discourse >= 2026.5.0-latest, < 2026.5.1
Published Jul 09, 2026
Tracked Since Jul 10, 2026