CVE-2026-35594 Vikunja Link Share JWT tokens remain valid for 72 hours after share deletion or permission downgrade
Attackers retain access to deleted or downgraded link shares for 72 hours because Vikunja trusts JWT claims without server-side validation.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-35594?
CVE-2026-35594 is a medium-severity vulnerability in go-vikunja vikunja, published on 10 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
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.
Weakness: CWE-613
Which versions are affected by CVE-2026-35594?
3 open source packages ship an affected version, including code.vikunja.io/api. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
code.vikunja.io/api Go | All versions | None |
code.vikunja.io/api Go | All versions | 2.3.0 |
code.vikunja.io/api Go | All versions | 2.3.0 |
Products include Vikunja Vikunja.
How do I fix CVE-2026-35594?
Upgrade code.vikunja.io/api to 2.3.0 or later.
Is CVE-2026-35594 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-35594 exists.
Other vulnerabilities in go-vikunja vikunja
- CVE-2026-28268 Vikunja Vulnerable to Account Takeover via Password Reset Token Reuse
- CVE-2026-27575 Vijkunja has Weak Password Policy Combined with Persistent Sessions After Password Change
- CVE-2026-25935 Vikunja Affected by XSS Via Task Preview
- CVE-2026-35595 Vikunja Affected by Privilege Escalation via Project Reparenting
- CVE-2026-33316 Vikunja’s Improper Access Control Enables Bypass of Administrator-Imposed Account Disablement
Sources
Also known as GHSA-96q5-xm3p-7m84, GO-2026-5276.