CVE-2026-42514: e-Sushrut OTP Information Disclosure Flaw

CVE-2026-42514 Overview

This vulnerability exists in e-Sushrut due to exposure of OTPs in plaintext within API responses. A remote attacker could exploit this vulnerability by intercepting API responses containing valid OTPs. Successful exploitation of this vulnerability could allow an attacker to impersonate the target user and gain unauthorized access to user accounts on the targeted system.

Critical Impact

Attackers can intercept plaintext OTPs from API responses, enabling account takeover and unauthorized access to sensitive healthcare system data.

Affected Products

• e-Sushrut Healthcare Management System

Discovery Timeline

• 2026-04-29 - CVE CVE-2026-42514 published to NVD
• 2026-04-29 - Last updated in NVD database

Technical Details for CVE-2026-42514

Vulnerability Analysis

CVE-2026-42514 is classified under CWE-319 (Cleartext Transmission of Sensitive Information), a vulnerability category where sensitive data is transmitted over an unprotected communication channel. In this case, e-Sushrut exposes One-Time Passwords (OTPs) in plaintext within API responses, creating a significant security gap in the authentication workflow.

The vulnerability is particularly concerning in a healthcare context where e-Sushrut systems manage sensitive patient data and medical records. An attacker positioned to intercept network traffic can capture valid OTPs and use them to bypass authentication mechanisms entirely.

Root Cause

The root cause of this vulnerability is improper handling of sensitive authentication tokens in API responses. Instead of implementing secure OTP delivery mechanisms where the OTP is never exposed in API responses (such as sending directly via SMS/email without echoing back), the application includes the plaintext OTP in the API response body. This design flaw violates the principle that sensitive authentication credentials should never traverse observable channels where they can be intercepted.

Attack Vector

The attack vector for CVE-2026-42514 is network-based, requiring no authentication or user interaction. An attacker can exploit this vulnerability by:

1. Positioning themselves to intercept network traffic between the client and the e-Sushrut server (e.g., man-in-the-middle attack, network sniffing on shared networks, or compromised network infrastructure)
2. Monitoring API responses during authentication flows when OTPs are generated
3. Capturing the plaintext OTP from the intercepted API response
4. Using the captured OTP to authenticate as the target user before the legitimate OTP expires

The vulnerability is exploited through passive network interception. When a user requests an OTP for authentication, the API response contains the OTP in cleartext. An attacker monitoring the network traffic can extract this OTP and use it to gain unauthorized access to the victim's account.

For technical details on this vulnerability, refer to the CERT-IN Advisory CIVN-2026-0207.

Detection Methods for CVE-2026-42514

Indicators of Compromise

• Multiple successful OTP authentications from different IP addresses within short time windows for the same user account
• Authentication events originating from unexpected geographic locations or IP ranges not associated with legitimate users
• Unusual patterns of failed login attempts followed by successful OTP-based authentication from different network segments

Detection Strategies

• Implement network monitoring to detect unencrypted API traffic containing authentication-related data patterns
• Deploy application-layer logging to track OTP generation events and correlate them with subsequent authentication attempts
• Configure SIEM rules to alert on multiple OTP usage attempts or rapid sequential authentication events

Monitoring Recommendations

• Enable detailed API access logging to capture all authentication-related requests and responses
• Monitor for suspicious network traffic patterns indicative of man-in-the-middle attacks or packet sniffing
• Implement real-time alerting for authentication anomalies such as concurrent logins or rapid geographic changes

How to Mitigate CVE-2026-42514

Immediate Actions Required

• Enforce TLS/HTTPS for all API communications to encrypt data in transit and prevent network interception
• Review and audit API response structures to ensure OTPs and other sensitive credentials are never included in response bodies
• Implement rate limiting on OTP generation endpoints to reduce the window of opportunity for exploitation
• Consider implementing IP-binding for OTP validation to ensure OTPs can only be used from the requesting IP address

Patch Information

Organizations should consult the CERT-IN Advisory CIVN-2026-0207 for official guidance on available patches and remediation steps. Contact your e-Sushrut vendor or support channel for the latest security updates addressing this vulnerability.

Workarounds

• Ensure all e-Sushrut deployments enforce HTTPS/TLS to encrypt API traffic, preventing plaintext OTP interception
• Implement network segmentation to limit exposure of e-Sushrut API traffic to trusted network zones only
• Deploy a Web Application Firewall (WAF) to monitor and filter suspicious API traffic patterns
• Consider implementing additional authentication factors beyond OTP until a permanent fix is applied

# Configuration example
# Enforce HTTPS on web server (nginx example)
server {
    listen 80;
    server_name e-sushrut.example.com;
    return 301 https://$server_name$request_uri;
}

server {
    listen 443 ssl;
    server_name e-sushrut.example.com;
    ssl_certificate /path/to/certificate.crt;
    ssl_certificate_key /path/to/private.key;
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_prefer_server_ciphers on;
}