Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Primary rating from GitHub Advisory · only source for this CVE.
CVSS VectorGitHub Advisory
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Lifecycle Timeline
4DescriptionGitHub Advisory
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.
AnalysisAI
Vikunja prior to version 2.3.0 fails to validate link share permissions against server state during JWT authentication, allowing attackers with revoked or downgraded JWT tokens to maintain the original access level for up to 72 hours. This affects self-hosted task management deployments where link shares are used for collaboration, enabling unauthorized information disclosure and modification of shared projects even after a project owner explicitly revokes or restricts access.
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Vulnerability AssessmentAI
| Risk Assessment | The CVSS 6.5 (Medium) score reflects the moderate but real-world impact: network-accessible, unauthenticated attack surface (AV:N, PR:N) with low complexity (AC:L), but limited scope (information disclosure and modification only, no system-wide impact). … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker obtains a Vikunja link share URL (e.g., shared by a collaborator or discovered via OSINT) that grants read access to a project. The project owner later realizes the link was leaked, revokes the share via the Vikunja UI, and believes access is terminated. … |
| Remediation | Vendor-released patch: Vikunja 2.3.0 and later. … Detailed patch versions, workarounds, and compensating controls in full report. |
Threat intelligence, references, and detailed analysis are available after sign-in.
Share
External POC / Exploit Code
Leaving vuln.today
EUVD-2026-21417
GHSA-96q5-xm3p-7m84