Vulnerability · Published Jun 26, 2026 · Assigned by GitHub_M

CVE-2026-52782OpenProject: IDOR through /projects/<A>/settings/project_storages/<A_ps_id> via PATCH parameter "storages_project_storage[project_folder_id]" leads to Access to Unauthorized Resources

Critical 9.9

In plain English

A critical-severity authorization bypass via user-controlled key in openproject from opf. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.

Severity (CVSS 3.1)9.9Critical

Exploit odds (30 days)0.5%top 60.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack tooling1Public PoC

Official description

OpenProject is open-source, web-based project management software. Prior to 17.3.3 and 17.4.1, there is an IDOR through /projects/<A>/settings/project_storages/<A_ps_id> via PATCH parameter "storages_project_storage[project_folder_id]" leads to Access to Unauthorized Resources. A project-admin in one project can hijack the managed Nextcloud or OneDrive folder of another project on the same storage by writing the victim project's project_folder_id into the attacker's Storages::ProjectStorage row. The next managed-folder sync overwrites the ACL on the referenced folder with the attacker project's user list. This vulnerability is fixed in 17.3.3 and 17.4.1.

Affected products (as reported)

Vendor	Product	Versions
opf	openproject	< 17.3.3>= 17.4.0, < 17.4.1

Weakness: CWE-639 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

References

https://github.com/opf/openproject/security/advisories/GHSA-3vpx-94qx-xpw6 x_refsource_CONFIRM