Vikunja has a Link Share Delete IDOR — Missing Project Ownership Check Allows Cross-Project Link Share Deletion
Priority LOW 30CWE-639Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-639.
Summary
Vikunja is an open-source self-hosted task management platform. Prior to version 2.2.1, the `DELETE /api/v1/projects/:project/shares/:share` endpoint does not verify that the link share belongs to the project specified in the URL. An attacker with admin access to any project can delete link shares from other projects by providing their own project ID combined with the target share ID. Version 2.2.1 patches the issue.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00261 17th percentileScored 2026-11-07
Fix Fixed vikunja (go-vikunja): 2.2.1code.vikunja.io/api (Go): 2.2.1
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- 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 | before 2.2.1 | 2.2.1 | Patch available | CNA |
| — | code.vikunja.io/api (Go) | before 2.2.1 | 2.2.1 | Patch available | GHSA-f95f-77jx-fcjc |
- vikunja Vendorgo-vikunja Affected before 2.2.1 Fixed in 2.2.1 Patch available CNA
- code.vikunja.io/api (Go) Vendor— Affected before 2.2.1 Fixed in 2.2.1 Patch available GHSA-f95f-77jx-fcjc
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:* | before 2.2.1 | Vulnerable | go-vikunja |
- cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:* Versions before 2.2.1 Vulnerable ·go-vikunja
Remediation
- Fix · CNA vikunja (go-vikunja) Fixed in 2.2.1
- Fix · GHSA-f95f-77jx-fcjc code.vikunja.io/api (Go) Fixed in 2.2.1 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-33700
- 2026-10-03 Alias added: GHSA-f95f-77jx-fcjc
References
More go-vikunja Vikunja vulnerabilities
- TI-2026-21967 Vijkunja has Weak Password Policy Combined with Persistent Sessions After Password Change CVSS 3.1CRITICAL 9.1
- TI-2026-26971 Vikunja ahs a TOTP Two-Factor Authentication Bypass via OIDC Login Path CVSS 3.1CRITICAL 9.1
- TI-2026-26060 Vikunja Vulnerable to Link Share Hash Disclosure via ReadAll Endpoint Enables Permission Escalation CVSS 3.1HIGH 7.5
- TI-2026-20965 Vikunja Affected by XSS Via Task Preview CVSS 4.0HIGH 8.6
- TI-2026-27698 Vikunja Affected by Privilege Escalation via Project Reparenting CVSS 3.1HIGH 8.3
- TI-2026-25727 Vikunja’s Improper Access Control Enables Bypass of Administrator-Imposed Account Disablement CVSS 3.1HIGH 8.1
Sources
- CVE-2026-33700 · CVE Program
- CVE-2026-33700 · NVD
- FIRST EPSS
- GHSA-f95f-77jx-fcjc · 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