Vulnerability · Published Apr 10, 2026 · Assigned by GitHub_M
CVE-2026-35594Vikunja Link Share JWT tokens remain valid for 72 hours after share deletion or permission downgrade
Medium 6.5
In plain English
A medium-severity security flaw in vikunja from go-vikunja. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 23% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | code.vikunja.io/api | 2.3.0 | GHSA-96q5-xm3p-7m84 |
| Go | code.vikunja.io/api | no fix listed | GO-2026-5276 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| go-vikunja | vikunja | < 2.3.0 |
Weakness: CWE-613 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
References
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-96q5-xm3p-7m84 x_refsource_CONFIRM
- https://github.com/go-vikunja/vikunja/pull/2581 x_refsource_MISC
- https://github.com/go-vikunja/vikunja/commit/379d8a5c19334ffe4846003f590e202c31a75479 x_refsource_MISC
- https://github.com/go-vikunja/vikunja/releases/tag/v2.3.0 x_refsource_MISC