Description
Vikunja is an open-source self-hosted task management platform. Prior to 2.3.0, Vikunja's link share authentication (GetLinkShareFromClaims in pkg/models/link_sharing.go) constructs authorization objects entirely from JWT claims without any server-side database validation. When a project owner deletes a link share or downgrades its permissions, all previously issued JWTs continue to grant the original permission level for up to 72 hours (the default service.jwtttl). This vulnerability is fixed in 2.3.0.
Affected products
vikunja: vikunja
References5
- github.com/go-vikunja/vikunja/security/advisories/GHSA-96q5-xm3… ExploitVendor Advisory
- github.com/go-vikunja/vikunja/security/advisories/GHSA-96q5-xm3… ExploitVendor Advisory
- github.com/go-vikunja/vikunja/commit/379d8a5c19334ffe4846003f59… Patch
- github.com/go-vikunja/vikunja/pull/2581 Issue Tracking
- github.com/go-vikunja/vikunja/releases/tag/v2.3.0 Release Notes
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 25 · as of 12 November 2026
- CWE
- CWE-613
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.