CVE-2026-42515: e-Sushrut Auth Bypass Vulnerability

CVE-2026-42515 Overview

CVE-2026-42515 is a high-severity Insecure Direct Object Reference (IDOR) vulnerability affecting e-Sushrut, a healthcare management system. The vulnerability stems from improper access control in resource access validation, allowing authenticated attackers to manipulate API request URL parameters to gain unauthorized access to sensitive patient information. This represents a significant privacy breach vector in healthcare environments where patient data confidentiality is paramount.

Critical Impact

Authenticated attackers can exploit improper access control to access sensitive patient health records and personal information by manipulating API parameters, potentially violating healthcare data protection regulations.

Affected Products

• e-Sushrut Healthcare Management System

Discovery Timeline

• April 29, 2026 - CVE-2026-42515 published to NVD
• April 29, 2026 - Last updated in NVD database

Technical Details for CVE-2026-42515

Vulnerability Analysis

This vulnerability is classified under CWE-639 (Authorization Bypass Through User-Controlled Key), a type of Insecure Direct Object Reference (IDOR) flaw. The core issue lies in the e-Sushrut application's failure to properly validate that an authenticated user has authorization to access specific patient records. When making API requests, the application relies on user-supplied parameters to identify which resources to retrieve, but does not adequately verify that the requesting user should have access to those specific resources.

In healthcare systems like e-Sushrut, this type of vulnerability is particularly dangerous because it can expose Protected Health Information (PHI), including patient medical records, diagnoses, treatment histories, and personal identification data. The network-accessible nature of this vulnerability combined with low attack complexity makes it exploitable by any authenticated user with basic knowledge of API manipulation.

Root Cause

The root cause of CVE-2026-42515 is the absence of proper authorization checks at the API level when processing resource requests. The application trusts user-supplied resource identifiers without verifying that the authenticated user has legitimate access rights to the requested patient data. This is a common pattern in applications that implement authentication but fail to enforce proper authorization controls on a per-resource basis.

Attack Vector

The attack vector for this vulnerability requires network access and low-privilege authentication. An attacker with valid credentials to the e-Sushrut system can manipulate parameters in API request URLs to reference patient records belonging to other users. The vulnerability does not require user interaction and can be exploited with readily available tools such as web proxies or browser developer tools.

For example, an authenticated attacker could intercept API requests and modify patient identifier parameters to enumerate and access records they should not be authorized to view. The attack is straightforward, requiring only the ability to capture and modify HTTP requests to the vulnerable API endpoints.

Detection Methods for CVE-2026-42515

Indicators of Compromise

• Unusual patterns of API requests from a single authenticated user accessing multiple patient records in rapid succession
• API access logs showing sequential or predictable patient identifier enumeration attempts
• Authenticated sessions accessing patient records outside their normal workflow or department scope
• Unexpected export or download requests for patient data from non-administrative accounts

Detection Strategies

• Implement API request logging and monitor for parameter manipulation patterns indicative of IDOR exploitation
• Configure alerting for authenticated users accessing patient records outside their assigned patient population
• Deploy web application firewall (WAF) rules to detect sequential parameter enumeration in API requests
• Enable audit logging for all patient record access with user attribution for forensic analysis

Monitoring Recommendations

• Monitor API access logs for anomalous patterns such as high-volume requests to patient data endpoints
• Implement real-time alerting for access attempts to patient records that fail authorization checks
• Review access logs regularly for any authenticated user accessing patient records outside their normal scope
• Establish baseline access patterns for each user role to identify deviation from normal behavior

How to Mitigate CVE-2026-42515

Immediate Actions Required

• Review and audit all API endpoints that handle patient data access for proper authorization validation
• Implement server-side access control checks that verify the authenticated user's authorization for each specific resource request
• Enable comprehensive logging of all patient data access for audit and forensic purposes
• Restrict access to the e-Sushrut application to trusted networks while implementing permanent fixes

Patch Information

Organizations using e-Sushrut should consult the CERT-IN Vulnerability Note CIVN-2026-0207 for official remediation guidance and any available patches from the vendor. Contact the e-Sushrut vendor directly for specific patch availability and deployment instructions.

Workarounds

• Implement additional authorization middleware or proxy layer to validate user access rights before forwarding API requests
• Apply network segmentation to restrict which systems and users can reach the vulnerable API endpoints
• Implement rate limiting on patient data API endpoints to slow potential enumeration attacks
• Consider temporarily restricting API access to administrative users only until a permanent fix is deployed

# Example: Implement network-level access restrictions for e-Sushrut API endpoints
# Configure firewall rules to restrict access to trusted IP ranges
iptables -A INPUT -p tcp --dport 443 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP

# Enable detailed access logging for patient data API endpoints
# Configure web server to log all parameters for audit purposes