CVE-2025-55740

MEDIUM
Published Aug 19, 2025 Modified Apr 15, 2026 CWE-1392

Description

nginx-defender is a high-performance, enterprise-grade Web Application Firewall (WAF) and threat detection system engineered for modern web infrastructure. This is a configuration vulnerability affecting nginx-defender deployments. Example configuration files config.yaml and docker-compose.yml contain default credentials (default_password: "change_me_please", GF_SECURITY_ADMIN_PASSWORD=admin123). If users deploy nginx-defender without changing these defaults, attackers with network access could gain administrative control, bypassing security protections. The issue is addressed in v1.5.0 and later.

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CVSS v3.1 Score

6.5
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Weakness Type (CWE)

CWE-1392 CWE-1392

References

Frequently Asked Questions

What is CVE-2025-55740? +
nginx-defender is a high-performance, enterprise-grade Web Application Firewall (WAF) and threat detection system engineered for modern web infrastructure. This is a configuration vulnerability affecting nginx-defender deployments. Example configuration files config.yaml and docker-compose.yml contain default credentials (default_password: "change_me_please", GF_SECURITY_ADMIN_PASSWORD=admin123). If users deploy nginx-defender without changing these defaults, attackers with network access could gain administrative control, bypassing security protections. The issue is addressed in v1.5.0 and later. It has a CVSS v3.1 base score of 6.5 (MEDIUM).
How severe is CVE-2025-55740? +
CVE-2025-55740 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
How do I check if I'm vulnerable to CVE-2025-55740? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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