CVE-2026-68581
Vikunja versions 0.22.0 through 2.3.0 fail to validate the principal type in API token management. Because user IDs and link-share IDs are independent numeric sequences and both resolve through a generic web.Auth.GetID() interface, a link-share JWT whose numeric ID equals a target user's ID is treated as that user by the /api/v1/tokens endpoints. An authenticated attacker can obtain a target's numeric user ID via authenticated user search, then create link shares on an attacker-writable project until the link-share sequence reaches that value, and use the resulting link-share JWT to list, create, and delete the target user's API tokens (including issuing a new token with attacker-chosen scopes under the target's permissions). Fixed in version 2.4.0.
- CVSS 4.0
- 8.6
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 8.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - EPSS
- 0.5% chance of exploitation in the next 30 days; higher than 39% of CVEs (scores of 2026-10-25)
- CWE
- CWE-863
- Published
- Modified
- Record from
- the NVD, synced
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-vvcv-vpph-h844 | Go | code.vikunja.io/api | >=0.22.0 <2.4.0 | 2.4.0 |
| GO-2026-6753 | Go | code.vikunja.io/api | >=0.22.0 | no fix published |
References
- https://github.com/go-vikunja/vikunja/commit/95b7e673fb5ee407498fa4b13e8b4c57847a4a0b
- https://github.com/go-vikunja/vikunja/commit/e6b25bd57b537ef9a72b5acdadf446ca5ef77bfa
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-vvcv-vpph-h844
- https://www.vulncheck.com/advisories/vikunja-through-authentication-bypass-via-principal-id-collision
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-vvcv-vpph-h844