Vulnerability · Published Jan 19, 2026 · Assigned by GitHub_M

CVE-2026-23721OpenProject users with "View Members" permission in any project can view all Group memberships

Medium 4.3

In plain English

A medium-severity missing authorization 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 0.2% (higher than 11% of all known vulnerabilities).

Severity (CVSS 3.1)4.3Medium

Exploit odds (30 days)0.2%top 88.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

OpenProject is an open-source, web-based project management software. When using groups in OpenProject to manage users, the group members should only be visible to users that have the View Members permission in any project that the group is also a member of. Prior to versions 17.0.1 and 16.6.5, due to a failed permission check, if a user had the View Members permission in any project, they could enumerate all Groups and view which other users are part of the group. The issue has been fixed in OpenProject 17.0.1 and 16.6.5. No known workarounds are available.

Affected products (as reported)

Vendor	Product	Versions
opf	openproject	< 16.6.5= 17.0.0

Weakness: CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

References

https://github.com/opf/openproject/security/advisories/GHSA-vj77-wrc2-5h5h x_refsource_CONFIRM