Missing authorization in go-vikunja vikunja
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-862.
Summary
Vikunja is an open-source self-hosted task management platform. From 2.3.0 until 2.4.0, a user with Write but not Admin permission on a shared child project can detach it from its parent hierarchy by submitting parent_project_id equal to 0 to POST /api/v1/projects/{project}. The Project.CanUpdate authorization check in pkg/models/project_permissions.go and UpdateProject logic in pkg/models/project.go only gate nonzero parent values, while UpdateProject always persists parent_project_id, so the explicit zero value bypasses the Admin requirement introduced for CVE-2026-35595. Detachment severs the recursive permission-inheritance chain and can disrupt the owner’s hierarchy and inherited collaborator access. This issue is fixed in version 2.4.0.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| go-vikunja | vikunja | 2.3.0 to before 2.4.0 | 2.4.0 | Patch available | CNA |
| — | code.vikunja.io/api (Go) | 2.3.0 to before 2.4.0 | 2.4.0 | Patch available | GHSA-44v6-7fxq-vgf4 |
- vikunja Vendorgo-vikunja Affected 2.3.0 to before 2.4.0 Fixed in 2.4.0 Patch available CNA
- code.vikunja.io/api (Go) Vendor— Affected 2.3.0 to before 2.4.0 Fixed in 2.4.0 Patch available GHSA-44v6-7fxq-vgf4
CPE names Threatist (inferred) · 1
Inferred from how NVD named this product before; not given by a source.
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:* | — | — | go-vikunja |
- cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:* Versions — — ·go-vikunja
Remediation
- Fix · CNA vikunja (go-vikunja) Fixed in 2.4.0
- Fix · GHSA-44v6-7fxq-vgf4 code.vikunja.io/api (Go) Fixed in 2.4.0 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-55064
- 2026-10-03 Alias added: GHSA-44v6-7fxq-vgf4
References
Other 5
- https://github.com/go-vikunja/vikunja/security/advisories/GHSA-44v6-7fxq-vgf4
- https://github.com/go-vikunja/vikunja/pull/3239
- https://github.com/go-vikunja/vikunja/commit/781ffac198548ae4f3d1febc613caed8e0e11d01
- https://github.com/go-vikunja/vikunja/releases/tag/v2.4.0
- https://github.com/go-vikunja/vikunja
More go-vikunja vulnerabilities
- TI-2026-40929 Authorization bypass in go-vikunja Vikunja CVSS 4.0CRITICAL 9.3
- TI-2026-21967 Vijkunja has Weak Password Policy Combined with Persistent Sessions After Password Change CVSS 3.1CRITICAL 9.1
- TI-2026-62115 Vikunja before 2.6.0 Privilege Escalation via Link Share Hash CVSS 4.0HIGH 8.7
- TI-2026-62108 Vikunja before 2.6.0 Authentication Bypass via CalDAV BasicAuth CVSS 4.0HIGH 8.7
- TI-2026-62107 Vikunja before 2.6.0 Authentication Bypass via Unthrottled API CVSS 4.0HIGH 8.7
- TI-2026-26971 Vikunja ahs a TOTP Two-Factor Authentication Bypass via OIDC Login Path CVSS 3.1CRITICAL 9.1
Sources
- CVE-2026-55064 · CVE Program
- CVE-2026-55064 · NVD
- FIRST EPSS
- GHSA-44v6-7fxq-vgf4 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences