# CVE-2023-26438: Server-side request forgery in OX App Suite

> Attackers can bypass network deny-lists via DNS cache timing to discover restricted infrastructure and service availability in OX App Suite.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A: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:** 2 Aug 2023
- **Updated:** 2 Aug 2024
- **Also known as:** GHSA-cp3q-q6mx-w79j

## What is CVE-2023-26438?

CVE-2023-26438 is a medium-severity server-side request forgery vulnerability in OX App Suite, published on 2 Aug 2023. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

External service lookups for a number of protocols were vulnerable to a time-of-check/time-of-use (TOCTOU) weakness, involving the JDK DNS cache. Attackers that were timing DNS cache expiry correctly were able to inject configuration that would bypass existing network deny-lists. Attackers could exploit this weakness to discover the existence of restricted network infrastructure and service availability. Improvements were made to include deny-lists not only during the check of the provided connection data, but also during use. No publicly available exploits are known.

Weakness: CWE-367 (Time-of-check Time-of-use (TOCTOU) Race Condition), CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2023-26438?

It affects 1 product.


Products: Open-Xchange Open-Xchange Appsuite Backend.

## How do I fix CVE-2023-26438?

No fix has been published for CVE-2023-26438 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-26438 being exploited?

There is no known exploitation of CVE-2023-26438 in the wild and no public exploit code.

## Other vulnerabilities in OX App Suite

- [CVE-2023-26451](https://insights.sbomify.com/CVE-2023-26451/): Weak cryptography in OX App Suite (high 7.5)
- [CVE-2023-26436](https://insights.sbomify.com/CVE-2023-26436/): Deserialization in OX App Suite (high 7.1)
- [CVE-2023-26428](https://insights.sbomify.com/CVE-2023-26428/): Missing authorization in OX App Suite (medium 6.5)
- [CVE-2023-26443](https://insights.sbomify.com/CVE-2023-26443/): SQL injection in OX App Suite (medium 5.5)
- [CVE-2023-26431](https://insights.sbomify.com/CVE-2023-26431/): Server-side request forgery in OX App Suite (medium 5.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-26438 and fix it if it is affected.

What it is: CVE-2023-26438 is a medium-severity server-side request forgery vulnerability in OX App Suite, published on 2 Aug 2023. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-26438 in the wild and no public exploit code.

Affected product: OX App Suite. 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-2023-26438/ (Markdown: https://insights.sbomify.com/CVE-2023-26438/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-26438
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-26438
- OSV: https://osv.dev/vulnerability/CVE-2023-26438

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-26438/
Summaries are generated and may contain mistakes; the official description above is the record.