# CVE-2026-45342: LinkAce: IDOR in Update Policies Allows Any Authenticated User to Overwrite Other Users' Links, Lists, Tags, and Notes

> Authenticated users can modify other users' links, lists, tags, and notes due to flawed authorization checks in LinkAce.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 28 May 2026
- **Updated:** 29 May 2026
- **Also known as:** GHSA-cj8f-h888-m57m

## What is CVE-2026-45342?

CVE-2026-45342 is a high-severity missing authorization vulnerability in Kovah LinkAce, published on 28 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

LinkAce is a self-hosted archive to collect website links. Prior to 2.5.6, LinkAce contains an Insecure Direct Object Reference vulnerability in the authorization policy layer that allows any authenticated user to modify resources owned by other users. The affected resource types are links, lists, tags, and notes. Both the web UI and the REST API are vulnerable. The root cause is in the update() methods of all four model policies: LinkPolicy, LinkListPolicy, TagPolicy, and NotePolicy. Each delegates to an access-check method (e.g., userCanAccessLink()) that returns true for any resource with non-private visibility, regardless of who owns it. This means any registered user can edit any public or internal resource across the entire instance. The delete() methods in the same policy files correctly require ownership via $link->user->is($user), which confirms that update was intended to be owner-only. The same flaw exists in the API layer through AuthorizesUserApiActions::userCanUpdateModel(), which mirrors the broken visibility-only check instead of the ownership check used by userCanDeleteModel(). Bulk edit operations via BulkEditController are also affected. This vulnerability is fixed in 2.5.6.

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

## Which versions are affected by CVE-2026-45342?


## How do I fix CVE-2026-45342?

No fix has been published for CVE-2026-45342 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-45342 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45342 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-45342 and fix it if it is affected.

What it is: CVE-2026-45342 is a high-severity missing authorization vulnerability in Kovah LinkAce, published on 28 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45342 exists.

Affected product: Kovah LinkAce. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-45342/ (Markdown: https://insights.sbomify.com/CVE-2026-45342/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-45342
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-45342
- OSV: https://osv.dev/vulnerability/CVE-2026-45342

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-45342/
Summaries are generated and may contain mistakes; the official description above is the record.