CVE-2026-30403

HighPublic PoC

Published: 19 March 2026

Published

19 March 2026

Modified

02 April 2026

KEV Added

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Patch

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CVSS Score 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Score 0.0007 22.3th percentile

Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-30403 is a high-severity Path Traversal (CWE-22) vulnerability in Wgstart Wgcloud. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 22.3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and SI-10 (Information Input Validation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 2 other techniques. What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-2 Flaw Remediation good match

prevent

Directly remediates the arbitrary file read flaw in wgcloud's test connection function through identification, reporting, and patching.

SI-10 Information Input Validation good match

prevent

Validates inputs to the vulnerable test connection function to block path traversal exploits enabling arbitrary file reads.

AC-3 Access Enforcement good match

prevent

Enforces access control policies to prevent unauthorized logical access to server files via the unauthenticated backend function.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

attack.mitre.org →

T1005 Data from Local System Collection

Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.

attack.mitre.org →

T1552.001 Credentials In Files Credential Access

Adversaries may search local file systems and remote file shares for files containing insecurely stored credentials.

attack.mitre.org →

Why these techniques?

Arbitrary file read (path traversal) in a network-accessible web/backend component directly enables remote exploitation of public-facing applications (T1190) and collection of arbitrary local files (T1005), including credential files (T1552.001).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

There is an arbitrary file read vulnerability in the test connection function of backend database management in wgcloud v3.6.3 and before, which can be used to read any file on the victim's server.

Deeper analysisAI

CVE-2026-30403 is an arbitrary file read vulnerability, classified under CWE-22, affecting the test connection function in the backend database management component of wgcloud versions 3.6.3 and earlier. This flaw allows unauthorized access to any file on the affected server. The vulnerability carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N) and was published on 2026-03-19T17:16:23.950.

An unauthenticated remote attacker can exploit this vulnerability over the network with low attack complexity and without requiring user interaction. Successful exploitation enables the attacker to read arbitrary files on the victim's server, potentially disclosing sensitive configuration data, credentials, or other critical information.

Advisories and discussions on mitigation are available in the following GitHub issues: https://github.com/TTTlw1024/qwe/issues/2 and https://github.com/tianshiyeben/wgcloud/issues/97.