CVE-2026-45775 Discourse: Cross-site backup access via path traversal in multisite local backups
An authenticated administrator in a multisite Discourse deployment can access backup files from other sites via path traversal.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45775?
CVE-2026-45775 is a medium-severity path traversal vulnerability in Discourse Discourse, published on 12 Jun 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official 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, a path traversal vulnerability in Discourse backup handling could allow an authenticated administrator on one site in a multisite deployment to access backup files belonging to another site when backups are stored locally. In affected configurations, an admin on Site A could potentially retrieve sensitive backup data from Site B (same host, multisite) by crafting a backup download request with a traversal payload. This issue has been patched in versions 2026.1.4, 2026.3.1, 2026.4.1, and 2026.5.0-latest.1.
Weakness: CWE-22
Which versions are affected by CVE-2026-45775?
1 open source package ship an affected version, including discourse. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
discourse Bitnami | From 2026.1.0 | 2026.1.4, 2026.3.1, 2026.4.1 |
Products include Discourse Discourse.
How do I fix CVE-2026-45775?
Upgrade discourse to a fixed version for your release line: 2026.1.4, 2026.3.1 or 2026.4.1.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-45775 being exploited?
There is no known exploitation of CVE-2026-45775 in the wild and no public exploit code.
Other vulnerabilities in Discourse Discourse
- CVE-2021-41163 RCE via malicious SNS subscription payload
- CVE-2022-36066 Discourse vulnerable to RCE via admins uploading maliciously zipped file
- CVE-2022-39356 Discourse user account takeover via email and invite link
- CVE-2023-22468 Discourse vulnerable to Cross-site Scripting in local oneboxes
- CVE-2026-27934 Discourse leaks private topic title and post excerpt via user action API endpoint
Sources
Also known as BIT-discourse-2026-45775, GHSA-5j6v-4x6g-9pg5.