# CVE-2026-52850: Docmost access control bypass in transclusion API

Source: https://junglewise.ai/threats/cve-2026-52850-docmost-is-open-source-collaborative-wiki-and-documentation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-24. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-52850 · Severity: medium · CVSS 4.3 · Published 2026-09-24

Docmost is an open-source wiki and documentation platform. An authenticated user without permission to access private spaces could exploit an API endpoint that looks up transcluded content blocks to retrieve confidential information and page metadata from restricted areas, bypassing the normal access controls that prevent this same user from viewing those pages directly.

Technologies: [Docmost](https://junglewise.ai/threats/technologies/docmost). Vendors: [Docmost](https://junglewise.ai/threats/vendors/docmost).

## Quick answers

**Is CVE-2026-52850 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-52850 being exploited in the wild.

**How severe is CVE-2026-52850?** Medium severity, with a CVSS score of 4.3, published 24 September 2026.

**Which products and versions are affected?** Docmost prior to 0.90.1.

**Is there a fix for CVE-2026-52850?** A patch was published on 2026-05-28: version 0.90.1 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-52850 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-52850?** Check whether you run Docmost at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An authenticated workspace member lacking private space membership can invoke the transclusion/sync-block lookup API by providing a known sourcePageId and transclusionId pair. The API endpoint fails to enforce private space membership checks before resolving and returning source page content and metadata, allowing information disclosure that the standard page access APIs correctly prevent. The vulnerability was patched in version 0.90.1.

## Affected products

- Docmost Docmost prior to 0.90.1

## Timeline

- 2026-09-24: disclosed
- 2026-05-28: patched: version 0.90.1 released

## References

- [https://github.com/docmost/docmost/commit/830b5b4d458a1302f42c8b68bff9ff559f6eb342](https://github.com/docmost/docmost/commit/830b5b4d458a1302f42c8b68bff9ff559f6eb342)
- [https://github.com/docmost/docmost/releases/tag/v0.90.1](https://github.com/docmost/docmost/releases/tag/v0.90.1)

## Related threats

- [Docmost ZIP bomb in page-import feature](https://junglewise.ai/threats/cve-2026-65827-docmost-is-open-source-collaborative-wiki-and-documentation)
- [Docmost privilege escalation in workspace invitation](https://junglewise.ai/threats/cve-2026-52853-docmost-is-open-source-collaborative-wiki-and-documentation)
- [Docmost authorization bypass in page export](https://junglewise.ai/threats/cve-2026-48073-docmost-is-open-source-collaborative-wiki-and-documentation)
- [Docmost path traversal in avatar and logo endpoint](https://junglewise.ai/threats/cve-2026-48072-docmost-is-open-source-collaborative-wiki-and-documentation)
- [Docmost arbitrary file deletion in avatar cleanup on local storage](https://junglewise.ai/threats/cve-2026-48070-docmost-is-open-source-collaborative-wiki-and-documentation)