Is CVE-2023-54403 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2023-54403 being exploited in the wild.

How severe is CVE-2023-54403?

High severity, with a CVSS score of 7.5, published 30 September 2026.

Which products and versions are affected?

Yonyou U8 CRM before V16.5 and V18.

Is there a fix for CVE-2023-54403?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2023-54403 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2023-54403?

Check whether you run Yonyou U8 CRM at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2023-54403: Yonyou U8 CRM arbitrary file read in getemaildata.php

CVE-2023-54403 · Severity: high · CVSS 7.5 · Published 2026-09-30

Yonyou U8 CRM is a customer relationship management system used by businesses to manage client interactions and data. An unauthenticated attacker can exploit a flaw in the getemaildata.php endpoint to read arbitrary files from the server, including sensitive configuration files that may contain database credentials or other sensitive information. This allows complete compromise of the underlying database and potentially other critical systems.

Vendors: Yonyou.

Quick answers

Is CVE-2023-54403 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2023-54403 being exploited in the wild.
How severe is CVE-2023-54403?: High severity, with a CVSS score of 7.5, published 30 September 2026.
Which products and versions are affected?: Yonyou U8 CRM before V16.5 and V18.
Is there a fix for CVE-2023-54403?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2023-54403 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2023-54403?: Check whether you run Yonyou U8 CRM at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability exists in the /ajax/getemaildata.php endpoint due to insufficient input validation on the filePath parameter combined with an authentication bypass via the DontCheckLogin=1 parameter. An unauthenticated attacker can craft requests to read arbitrary files outside the web application directory on the affected server. The flaw enables path traversal attacks to access sensitive files such as configuration files containing database credentials.

Affected products

Yonyou U8 CRM before V16.5 and V18

Timeline

2023-10-14: disclosed: Exploitation evidence first observed by Shadowserver Foundation
2026-09-30: advisory

References

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