# CVE-2026-39957: Missing authorization in Lychee

> Authenticated users can retrieve private album sharing metadata from other users due to a SQL logic error in the sharing controller.

- **Severity:** Low 2.3 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/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:** 9 Apr 2026
- **Updated:** 9 Apr 2026
- **Also known as:** GHSA-4v4c-g2jv-4g25

## What is CVE-2026-39957?

CVE-2026-39957 is a low-severity missing authorization vulnerability in LycheeOrg Lychee, published on 9 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Lychee is a free, open-source photo-management tool. Prior to 7.5.4, a SQL operator-precedence bug in SharingController::listAll() causes the orWhereNotNull('user_group_id') clause to escape the ownership filter applied by the when() block. Any authenticated non-admin user with upload permission who owns at least one album can retrieve all user-group-based sharing permissions across the entire instance, including private albums owned by other users. This vulnerability is fixed in 7.5.4.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-39957?

It affects 1 product.


Products: Lycheeorg Lychee.

## How do I fix CVE-2026-39957?

No fix has been published for CVE-2026-39957 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-39957 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-39957 exists.

## Other vulnerabilities in LycheeOrg Lychee

- [CVE-2023-52082](https://insights.sbomify.com/CVE-2023-52082/): Lychee is vulnerable to an SQL Injection in explain DB queries. (high 8.8)
- [CVE-2024-25808](https://insights.sbomify.com/CVE-2024-25808/): Cross-site request forgery in n/a (high 8.3)
- [CVE-2024-25807](https://insights.sbomify.com/CVE-2024-25807/): Cross-site scripting in n/a (medium 6.1)
- [CVE-2021-43675](https://insights.sbomify.com/CVE-2021-43675/): Cross-site scripting in n/a (medium 6.1)
- [CVE-2026-33537](https://insights.sbomify.com/CVE-2026-33537/): Lychee has SSRF bypass via incomplete IP validation in Photo::fromUrl — loopback and link-local IPs not blocked (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-39957 and fix it if it is affected.

What it is: CVE-2026-39957 is a low-severity missing authorization vulnerability in LycheeOrg Lychee, published on 9 Apr 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-2026-39957 exists.

Affected product: LycheeOrg Lychee. 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-2026-39957/ (Markdown: https://insights.sbomify.com/CVE-2026-39957/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-39957
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-39957
- OSV: https://osv.dev/vulnerability/CVE-2026-39957

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-39957/
Summaries are generated and may contain mistakes; the official description above is the record.