# CVE-2026-33700: Vikunja has a Link Share Delete IDOR — Missing Project Ownership Check Allows Cross-Project Link Share Deletion

> An attacker with admin access to any project can delete link shares from other projects due to missing ownership verification.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Mar 2026
- **Updated:** 24 Mar 2026
- **Also known as:** GHSA-f95f-77jx-fcjc, GO-2026-4850

## What is CVE-2026-33700?

CVE-2026-33700 is a medium-severity missing authorization vulnerability in go-vikunja vikunja, published on 24 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

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.

Weakness: CWE-639 (Authorization Bypass Through User-Controlled Key)

## Which versions are affected by CVE-2026-33700?

3 open source packages ship an affected version, including code.vikunja.io/api. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `code.vikunja.io/api` | Go | All versions | None |
| `code.vikunja.io/api` | Go | All versions | 2.2.1 |
| `code.vikunja.io/api` | Go | All versions | 2.2.1 |

Products: Vikunja Vikunja.

## How do I fix CVE-2026-33700?

Upgrade code.vikunja.io/api to 2.2.1 or later.

## Is CVE-2026-33700 being exploited?

There is no known exploitation of CVE-2026-33700 in the wild and no public exploit code.

## Other vulnerabilities in go-vikunja vikunja

- [CVE-2026-28268](https://insights.sbomify.com/CVE-2026-28268/): Vikunja Vulnerable to Account Takeover via Password Reset Token Reuse (critical 9.8)
- [CVE-2026-27575](https://insights.sbomify.com/CVE-2026-27575/): Vijkunja has Weak Password Policy Combined with Persistent Sessions After Password Change (critical 9.1)
- [CVE-2026-25935](https://insights.sbomify.com/CVE-2026-25935/): Vikunja Affected by XSS Via Task Preview (high 8.6)
- [CVE-2026-35595](https://insights.sbomify.com/CVE-2026-35595/): Vikunja Affected by Privilege Escalation via Project Reparenting (high 8.3)
- [CVE-2026-33316](https://insights.sbomify.com/CVE-2026-33316/): Vikunja’s Improper Access Control Enables Bypass of Administrator-Imposed Account Disablement (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-33700 and fix it if it is affected.

What it is: CVE-2026-33700 is a medium-severity missing authorization vulnerability in go-vikunja vikunja, published on 24 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-33700 in the wild and no public exploit code.

Affected packages and fixed versions:
- code.vikunja.io/api (Go): affected all versions; no fix listed
- code.vikunja.io/api (Go): affected all versions; fixed in 2.2.1
- code.vikunja.io/api (Go): affected all versions; fixed in 2.2.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-33700/ (Markdown: https://insights.sbomify.com/CVE-2026-33700/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-33700
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-33700
- OSV: https://osv.dev/vulnerability/CVE-2026-33700

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-33700/
Summaries are generated and may contain mistakes; the official description above is the record.