# CVE-2023-54398: Yonyou U8 Cloud Java Deserialization RCE via FileManageServlet

> Unauthenticated attackers can execute arbitrary OS commands in Yonyou U8 Cloud via unsafe Java deserialization in FileManageServlet.

- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Sep 2026
- **Updated:** 15 Sep 2026
- **Also known as:** GHSA-r89p-qrrf-vpmc

## What is CVE-2023-54398?

CVE-2023-54398 is a critical unsafe deserialization vulnerability in Yonyou U8 Cloud, published on 15 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Yonyou U8 Cloud contains an unauthenticated Java deserialization vulnerability in the nc.impl.pub.filesystem.FileManageServlet component that allows remote unauthenticated attackers to execute arbitrary OS commands by sending a serialized payload via POST request. Attackers can exploit the doAction method, which passes raw HTTP request body data directly to ObjectInputStream.readObject() without filtering, to achieve remote code execution. Exploitation evidence was first observed by the Shadowserver Foundation on 2025-02-13.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2023-54398?


## How do I fix CVE-2023-54398?

No fix has been published for CVE-2023-54398 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-54398 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-54398 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-54398 and fix it if it is affected.

What it is: CVE-2023-54398 is a critical unsafe deserialization vulnerability in Yonyou U8 Cloud, published on 15 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-54398 exists.

Affected product: Yonyou U8 Cloud. 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-2023-54398/ (Markdown: https://insights.sbomify.com/CVE-2023-54398/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-54398
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-54398
- OSV: https://osv.dev/vulnerability/CVE-2023-54398

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From sbomify Insights: https://insights.sbomify.com/CVE-2023-54398/
Summaries are generated and may contain mistakes; the official description above is the record.