CVE-2026-91157 HIGH

CVE-2026-91157: Discourse: Media uploads remain publicly accessible after category permissions are restricted

Vendor Discourse
Product discourse
Weakness CWE-200 · Info exposure
Published October 14, 2026
Last update October 20, 2026
View on NVD All CVEs

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality High
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

What the vulnerability does

01Description

Discourse is an open-source discussion platform. Prior to 2026.9.0, 2026.8.1, 2026.7.3, and 2026.1.9, sites with secure uploads enabled did not reconcile existing upload security metadata when a previously public category became read-restricted or when category permissions changed during a bulk import. Media and attachments uploaded while the category was public retained a public accessibility flag and remained reachable by anonymous users through their short upload URLs, including uploads associated with deleted topics. This issue is fixed in versions 2026.9.0, 2026.8.1, 2026.7.3, and 2026.1.9.

Key dates

02Disclosure timeline

October 14, 2026 CVE published
October 20, 2026 Record updated

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04Related CVE

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