CVE-2023-54400: Fumeng Cloud SQL Injection

Are You Affected?

Fumasoft Fumeng Cloud is affected when its AjaxMethod.ashx endpoint exposes the getEmpByname action and accepts attacker-controlled input through the Name parameter. The vulnerable functionality reportedly reaches a Microsoft SQL Server backend without safely separating SQL code from user-supplied data.

The available records do not identify a specific vulnerable release range such as “1.2.0 through 1.4.7,” and they do not name a fixed version. Do not treat an installed version as safe merely because it is newer than an internally selected baseline. Confirm the exact product build with Fumasoft or the responsible integrator, then obtain written remediation guidance.

Organizations should assume exposure if Fumeng Cloud is internet-accessible and the endpoint is reachable without authentication. Internal-only deployment reduces the attack surface but does not eliminate risk: compromised user workstations, VPN access, partner networks, and other systems on the same trusted network may still reach the application.

Analyst’s Take: The first priority is exposure reduction, not version guessing. Shadowserver-reported exploitation, public PoC material, and automated detection content make an internet-reachable endpoint a higher-priority investigation target, even though no authoritative fixed version is identified.

The Fix, If You’re in a Hurry

No authoritative vendor fixed version was identified in the supplied NVD and reference materials. There is therefore no defensible upgrade command such as upgrade fumeng-cloud --version X to provide, and administrators should not invent or infer a safe release number. Contact Fumasoft or the system integrator for an official hotfix or patched build, record the supplied build number, and verify that AjaxMethod.ashx no longer processes injectable input after remediation.

Until a vendor fix is confirmed, remove unnecessary network exposure. Place the application behind an authenticated VPN or private network, restrict access to known administrative source ranges, and block direct internet traffic to the application. If the vulnerable endpoint is not required for business operations, disable it at the application or web-server layer after testing dependent functionality.

For organizations reviewing remote-access controls, the secure self-hosted services checklist provides additional guidance on reducing exposure, segmenting administrative access, and validating compensating controls. A commercial VPN may also be useful for approved remote administration, but it should supplement—not replace—network segmentation and access controls: Check NordVPN pricing →

Technical Notes

A concrete IIS workaround is to deny direct access to the endpoint. Apply this only if the endpoint can be disabled without breaking required application functions, and test it in a staging environment first:

<configuration>
  <location path="AjaxMethod.ashx">
    <system.webServer>
      <security>
        <authorization>
          <remove users="*" />
          <add accessType="Deny" users="*" />
        </authorization>
      </security>
    </system.webServer>
  </location>
</configuration>

If the application must remain available, restrict the site at the network layer instead. For example, a Windows host firewall rule can block inbound HTTP and HTTPS traffic from untrusted networks, but the source ranges must be replaced with the organization’s approved administration or application networks:

New-NetFirewallRule `
  -DisplayName "Restrict Fumeng Cloud Web Access" `
  -Direction Inbound `
  -Action Block `
  -Protocol TCP `
  -LocalPort 80,443 `
  -RemoteAddress "Internet"

The RemoteAddress "Internet" value is illustrative and may not be accepted as a valid Windows Firewall address object in every deployment. Use explicit CIDR ranges or enforce the restriction at the perimeter firewall, reverse proxy, or VPN gateway. WAF rules that block SQL metacharacters and UNION patterns can reduce opportunistic scanning, but they are compensating controls, not a patch.

How This Vulnerability Works

CVE-2023-54400 is a server-side SQL injection vulnerability. A remote user can submit input to the Name parameter of the getEmpByname action through AjaxMethod.ashx. The application reportedly incorporates that input into a Microsoft SQL Server query without sufficient parameterization or equivalent validation.

The reported exploitation technique is UNION-based SQL injection. In a UNION attack, an attacker attempts to append a second query to the application’s original database query. If the resulting column structure and data types align, the application may return database values in its normal response. An attacker can use this behavior to test query structure, identify database metadata, and retrieve records.

The impact depends on the database account used by Fumeng Cloud and the privileges available to the application. Potential outcomes include disclosure of employee and application data, schema enumeration, modification or deletion of records, and follow-on compromise. SQL injection alone does not prove operating-system compromise, but excessive SQL Server privileges, unsafe database configuration, or additional application weaknesses can increase the blast radius.

Technical Notes

The vulnerable request path and parameter names defenders should search for are:

/AjaxMethod.ashx
getEmpByname
Name=

Do not copy exploit payloads into production testing. Detection and validation should be performed with authorized, non-destructive requests or with the referenced Nuclei template under an approved change and testing process.

Severity, Explained

The NVD-assigned base score is 9.8 Critical. The supplied NVD response did not include the CVSS vector string, so the exact component values should be confirmed directly in the NVD record before publication or formal risk scoring. The available facts establish the major severity drivers: the attack is remote, authentication is not required, and successful exploitation can affect confidentiality, integrity, and potentially availability.

The likely practical interpretation is that an attacker does not need an account or a privileged network position to send a crafted request. SQL injection can expose sensitive data and permit database changes, while the availability impact depends on the attacker’s database permissions and actions. Do not label the vector as an official CVSS string unless it has been verified against the authoritative record.

CVSS is a prioritization aid, not an exploitability guarantee. For this vulnerability, the risk is elevated by the reported public PoC, the existence of automated detection material, and the report of exploitation evidence from Shadowserver. The absence of a CISA Known Exploited Vulnerabilities listing does not override those signals.

Is It Being Exploited?

Yes. The NVD description reports that the Shadowserver Foundation observed exploitation evidence on 2023-10-18. This is evidence of real-world exploitation activity, although the available material does not provide a complete campaign description, attacker attribution, victim list, or a detailed request-level timeline.

A public PoC also exists. The NVD references a Goby PoC hosted in the emadshanab/goby-poc GitHub repository and a ProjectDiscovery Nuclei template for the Fumeng Cloud SQL injection. These references indicate that both proof-of-concept and automated detection material are publicly available.

CVE-2023-54400 is not listed in the CISA KEV catalog according to the supplied lookup. That status means there is no current KEV due date or required-action entry for this CVE; it does not mean exploitation is absent. Defenders should prioritize the reported exploitation evidence and public tooling rather than waiting for KEV inclusion.

The supplied research note does not include an independently verified count of news or social-media mentions, and the EPSS percentile was not provided. The social and EPSS metadata in this article should therefore not be treated as authoritative prevalence or probability measurements.