CVE-2025-40646: Energycrm Energy CRM Information Disclosure

CVE-2025-40646 Overview

CVE-2025-40646 is an information disclosure vulnerability affecting Viday, a product of Energycrm. The flaw exposes sensitive customer data through JSON Web Tokens (JWTs) transmitted in HTTP requests. An attacker with access to the adjacent network can intercept these requests and decode the JWT payload to read sensitive user information. The weakness maps to [CWE-200] (Exposure of Sensitive Information to an Unauthorized Actor).

Critical Impact
Attackers positioned on an adjacent network can harvest customer information embedded in JWT payloads, enabling follow-on identity abuse and targeted attacks against application users.

Affected Products

Energycrm Energy CRM (energy_crm) version 2025
Viday application component relying on JWT-based session handling
Deployments transmitting JWTs over unprotected HTTP channels

Discovery Timeline

2025-10-02 - CVE-2025-40646 published to the National Vulnerability Database (NVD)
2026-10-12 - Last updated in NVD database

Technical Details for CVE-2025-40646

Vulnerability Analysis

Viday issues JSON Web Tokens that carry sensitive customer information inside the token payload. JWT payloads are only Base64URL-encoded, not encrypted, so any party able to observe the token can decode the claims directly. The application transmits these tokens over HTTP requests that an adjacent-network attacker can capture through techniques such as ARP spoofing, rogue wireless access points, or a man-in-the-middle (MITM) position on the local segment.

User interaction is required for exploitation because the attacker depends on legitimate client traffic flowing through the observation point. Once a token is captured, the attacker reads customer attributes directly from the payload, with no need to break the token signature. Confidentiality is affected while integrity and availability are not, which aligns with the information-disclosure classification.

Root Cause

The root cause is the inclusion of sensitive personal data as claims inside the JWT payload combined with insufficient transport protection. JWTs should carry only non-sensitive identifiers unless the token is encrypted using JWE or protected by strict transport security. The current design treats the signed payload as confidential when it is, by specification, publicly readable.

Attack Vector

Exploitation requires the attacker to be on an adjacent network with the ability to intercept HTTP traffic generated by a Viday user session. The attacker observes authenticated requests, extracts the Authorization: Bearer <token> header or equivalent cookie, and decodes the payload segment. No credentials or privileges are needed on the application itself. See the INCIBE security notice on Viday vulnerabilities for additional vendor context.

Detection Methods for CVE-2025-40646

Indicators of Compromise

Unexpected ARP table changes or duplicate MAC addresses on segments where Viday clients operate.
Repeated access to Viday endpoints from source IP addresses not associated with legitimate user devices.
JWTs observed in plaintext HTTP traffic captures containing personally identifiable information in the payload.

Detection Strategies

Inspect network captures for Viday session tokens and decode the payload to confirm which claims are exposed.
Correlate authentication events with unusual client fingerprints, user-agent mismatches, or geo-inconsistent IP addresses.
Deploy network intrusion detection signatures that flag Viday JWTs transmitted over cleartext HTTP.

Monitoring Recommendations

Monitor wireless and LAN segments for MITM indicators such as gratuitous ARP floods and rogue DHCP responses.
Log all authentication and session-refresh events in Viday and alert on reuse of a token from multiple IP addresses.
Forward web and proxy logs to a centralized analytics platform for behavioral review of Viday session activity.

How to Mitigate CVE-2025-40646

Immediate Actions Required

Enforce HTTPS with HTTP Strict Transport Security (HSTS) for all Viday client-server communication.
Rotate signing keys and invalidate active JWTs after upgrading, forcing users to reauthenticate.
Audit JWT payloads and remove any personally identifiable or sensitive customer claims.

Patch Information

No vendor patch URL is listed in the CVE record at the time of writing. Operators of Energycrm Energy CRM 2025 should contact the vendor and consult the INCIBE advisory for fixed-version guidance.

Workarounds

Terminate Viday HTTP traffic at a reverse proxy that enforces TLS 1.2 or later and rejects cleartext connections.
Restrict Viday access to trusted network segments or require a VPN for remote users to reduce adjacent-network exposure.
Shorten JWT lifetimes and move sensitive data server-side, referencing it by opaque identifier within the token.

bash

# Example nginx configuration enforcing TLS and HSTS for Viday
server {
    listen 80;
    server_name viday.example.com;
    return 301 https://$host$request_uri;
}

server {
    listen 443 ssl http2;
    server_name viday.example.com;

    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers HIGH:!aNULL:!MD5;
    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;

    location / {
        proxy_pass http://viday_backend;
        proxy_set_header X-Forwarded-Proto https;
    }
}