# CVE-2026-33644: Server-side request forgery in Lychee

> Attackers can bypass SSRF protections in Lychee via DNS rebinding to access internal network resources.

- **Severity:** Low 2.3 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/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:** 26 Mar 2026
- **Updated:** 30 Mar 2026
- **Also known as:** GHSA-5245-4p8c-jwff

## What is CVE-2026-33644?

CVE-2026-33644 is a low-severity server-side request forgery vulnerability in LycheeOrg Lychee, published on 26 Mar 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 version 7.5.2, the SSRF protection in `PhotoUrlRule.php` can be bypassed using DNS rebinding. The IP validation check (line 86-89) only activates when the hostname is an IP address. When a domain name is used, `filter_var($host, FILTER_VALIDATE_IP)` returns `false`, skipping the entire check. Version 7.5.2 patches the issue.

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2026-33644?

It affects 1 product.


Products: Lycheeorg Lychee.

## How do I fix CVE-2026-33644?

No fix has been published for CVE-2026-33644 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-33644 being exploited?

There is no known exploitation of CVE-2026-33644 in the wild and no public exploit code.

## 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-2026-33644 and fix it if it is affected.

What it is: CVE-2026-33644 is a low-severity server-side request forgery vulnerability in LycheeOrg Lychee, published on 26 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-33644 in the wild and no public exploit code.

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-2026-33644/ (Markdown: https://insights.sbomify.com/CVE-2026-33644/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-33644
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-33644
- OSV: https://osv.dev/vulnerability/CVE-2026-33644

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-33644/
Summaries are generated and may contain mistakes; the official description above is the record.