CVE-2025-41240: Bitnami Helm Charts Info Disclosure Flaw

CVE-2025-41240 Overview

CVE-2025-41240 is a critical information disclosure vulnerability affecting three Bitnami Helm charts that mount Kubernetes Secrets under a predictable path (/opt/bitnami/*/secrets) located within the web server document root. This misconfiguration allows unauthenticated remote attackers to retrieve sensitive credentials via HTTP/S requests to specific URLs when the application is exposed externally.

The vulnerability is classified as CWE-552 (Files or Directories Accessible to External Parties), a serious configuration flaw that can lead to complete compromise of the affected deployment and potentially the broader Kubernetes cluster.

Critical Impact

Remote attackers can access sensitive credentials including database passwords, API keys, and service account tokens without authentication, potentially leading to complete system compromise.

Affected Products

• Bitnami Helm charts with default usePasswordFiles=true configuration
• Deployments exposing the web server externally
• Kubernetes environments using affected chart versions

Discovery Timeline

• 2025-07-24 - CVE CVE-2025-41240 published to NVD
• 2025-07-25 - Last updated in NVD database

Technical Details for CVE-2025-41240

Vulnerability Analysis

This vulnerability stems from a fundamental misconfiguration in how Bitnami Helm charts handle Kubernetes Secrets. The affected charts mount sensitive credential files directly into the web server's document root hierarchy, making them accessible to anyone who can reach the web server.

The core issue lies in the default behavior when usePasswordFiles=true is configured. This setting instructs the Helm chart to mount Kubernetes Secrets as files within the container filesystem at predictable paths under /opt/bitnami/*/secrets. Since this path resides within the web server's document root, any files placed there become directly accessible via HTTP/S requests.

An attacker with network access to the exposed application can enumerate and retrieve these secret files by crafting requests to the known secret paths. This could expose database credentials, API tokens, encryption keys, and other sensitive configuration data.

Root Cause

The root cause is improper file placement during Helm chart deployment. Kubernetes Secrets are mounted at a filesystem location that the web server is configured to serve, violating the principle of least privilege and secure-by-default configuration. The predictable path structure (/opt/bitnami/*/secrets) makes exploitation straightforward once an attacker identifies that a vulnerable Bitnami deployment is in use.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction. An attacker can exploit this vulnerability by:

1. Identifying an externally accessible Bitnami deployment (through banner grabbing, response headers, or other fingerprinting techniques)
2. Crafting HTTP/S requests to the predictable secret paths under /opt/bitnami/*/secrets
3. Retrieving plaintext credentials from the mounted secret files
4. Using the obtained credentials to access databases, APIs, or other connected services

The attack is particularly severe because it requires no special privileges and can be performed by any network attacker with access to the exposed web application.

Detection Methods for CVE-2025-41240

Indicators of Compromise

• Unusual HTTP/S requests targeting /opt/bitnami/*/secrets paths in web server access logs
• Access patterns showing enumeration attempts across multiple secret file paths
• Unexpected authentication from external sources using legitimate credentials
• Anomalous database or API access patterns following credential exposure

Detection Strategies

• Monitor web server access logs for requests containing /secrets or targeting paths under /opt/bitnami/
• Implement web application firewall (WAF) rules to block access to sensitive filesystem paths
• Deploy intrusion detection systems (IDS) with signatures for secret enumeration attempts
• Review Kubernetes audit logs for unexpected secret access or modifications

Monitoring Recommendations

• Configure alerting for any HTTP responses that return content from secret paths
• Monitor network traffic for credential exfiltration patterns
• Implement file integrity monitoring on secret mount points within containers
• Enable comprehensive logging for all Kubernetes secret access events

How to Mitigate CVE-2025-41240

Immediate Actions Required

• Audit all Bitnami Helm deployments to identify those using the vulnerable default configuration
• Restrict network access to affected applications until patches can be applied
• Rotate all credentials that may have been exposed through this vulnerability
• Review access logs to determine if exploitation has already occurred

Patch Information

Refer to the GitHub Security Advisory (GHSA-wgg9-9qgw-529w) for specific patch versions and remediation guidance from Bitnami. Organizations should upgrade to patched Helm chart versions as soon as they become available.

Workarounds

• Set usePasswordFiles=false if your application supports environment variable-based credential injection
• Configure web server rules to explicitly deny access to the /opt/bitnami/*/secrets path hierarchy
• Implement network policies to restrict external access to affected deployments
• Use Kubernetes NetworkPolicies to limit ingress traffic to trusted sources only

# Example: Deny access to secrets path in NGINX configuration
location ~ /secrets {
    deny all;
    return 404;
}