medium4.3
CVE-2026-91981
Vikunja versions before 2.6.0 fail to properly validate link-share tokens in the v2 API user search endpoints.
Impact
Vikunja versions before 2.6.0 fail to properly validate link-share tokens in the v2 API user search endpoints. Attackers with a read-only share link can enumerate project users via the projects endpoint and confirm arbitrary usernames exist via the global search endpoint.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | code.vikunja.io/api | <= 2.5.0 | 2.6.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-vfxw-3x8p-2vjr
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-vfxw-3x8p-2vjr
- https://nvd.nist.gov/vuln/detail/CVE-2026-91981
- https://github.com/go-vikunja/vikunja/pull/3688
- https://github.com/go-vikunja/vikunja/releases/tag/v2.6.0
- https://www.vulncheck.com/advisories/vikunja-before-2.6.0-user-enumeration-via-v2-api