CVE-2026-90598: E-commerce SpringBoot Auth Bypass Flaw

CVE-2026-90598 Overview

CVE-2026-90598 is an authorization bypass vulnerability in the jaygajera17/E-commerce-project-springBoot application, an open-source Spring Boot e-commerce platform. The flaw resides in the UserController.updateUser function within UserController.java. An authenticated attacker can manipulate the userid parameter to modify accounts belonging to other users, an Insecure Direct Object Reference (IDOR) pattern classified as [CWE-285] Improper Authorization. The issue is exploitable remotely over the network. A public proof-of-concept script is available, and the fix pull request has not yet been merged into the rolling-release codebase.

Critical Impact

Any authenticated user can send crafted requests to overwrite other users' profile data by supplying an arbitrary userid value.

Affected Products

• jaygajera17/E-commerce-project-springBoot (rolling release)
• All revisions up to and including commit 5e74a46b4b70623d0e4a0c9c4aee3bd1777185d2
• The UserController.java component exposing the updateUser endpoint

Discovery Timeline

• 2026-09-13 - CVE-2026-90598 published to NVD
• 2026-09-16 - Last updated in NVD database

Technical Details for CVE-2026-90598

Vulnerability Analysis

The updateUser handler in UserController.java accepts a userid argument from the incoming request and uses it to locate and update the target user record. The controller does not verify that the authenticated session owner matches the userid being modified. As a result, a low-privilege authenticated user can substitute another user's identifier and update that account.

This is a textbook Insecure Direct Object Reference. The application trusts a client-supplied identifier as an authorization decision input, violating the principle that authorization must be enforced server-side against the current session context. Successful exploitation yields limited integrity, confidentiality, and availability impact against individual user records rather than the underlying host.

Root Cause

The root cause is a missing authorization check between the authenticated principal and the resource identifier passed to UserController.updateUser. The application resolves the target user by the request-supplied userid field instead of deriving it from the authenticated session or JWT claims. No ownership or role-based access control (RBAC) predicate is applied before persisting the update.

Attack Vector

Exploitation requires network access to the application and a valid, low-privileged authenticated session. The attacker submits an HTTP request to the update endpoint with the userid parameter set to a victim's identifier and arbitrary values in the profile fields. The server processes the update against the victim account.

A public proof-of-concept script demonstrating the attack is published at GitHub PoC Script. See the GitHub Issue #172 and the pending GitHub Pull Request #174 for full technical detail.

Detection Methods for CVE-2026-90598

Indicators of Compromise

• HTTP requests to the updateUser endpoint where the userid parameter does not match the authenticated session's user identifier.
• Unexpected changes to user profile fields (email, address, password) that were not initiated by the account owner.
• Repeated update requests iterating through sequential userid values from a single session, indicating enumeration.

Detection Strategies

• Instrument the UserController.updateUser method to log both the authenticated principal and the incoming userid, then alert when they differ.
• Deploy a web application firewall (WAF) rule that inspects requests to the update endpoint and blocks mismatches between session identity and body parameters.
• Correlate authentication logs with user-profile mutation events to detect one-to-many session-to-account write patterns.

Monitoring Recommendations

• Track anomalous volumes of profile update requests per session, especially requests touching multiple distinct userid values.
• Monitor application logs for successful updates followed by user-reported account changes or password reset requests.
• Retain HTTP request bodies for the update endpoint for forensic replay during incident response.

How to Mitigate CVE-2026-90598

Immediate Actions Required

• Restrict public exposure of the application until a patch is applied; place it behind authenticated network controls if possible.
• Apply the code change proposed in GitHub Pull Request #174 as a private fork build if the upstream merge is still pending.
• Audit user account records for unauthorized modifications made since the vulnerable code was deployed.

Patch Information

At the time of publication, no released patch exists. The project uses a rolling-release model, and the fix awaits acceptance in GitHub Pull Request #174. Operators should track the upstream E-commerce-project-springBoot repository and rebuild once the fix merges. Additional advisory context is available at VulDB CVE-2026-90598.

Workarounds

• Modify UserController.updateUser to derive the target user identifier from the authenticated Principal or JWT claim rather than from the request body.
• Add a server-side ownership check that rejects the request when the session user does not match the requested userid, unless the caller holds an administrative role.
• Deploy a reverse-proxy or WAF rule that enforces the session-to-userid binding for the update endpoint until code-level remediation is deployed.

# Configuration example: sample Spring Security check to enforce ownership
# Add to UserController.updateUser before persisting the update:
#   if (!authentication.getName().equals(existingUser.getUsername())
#       && !authentication.getAuthorities().contains(new SimpleGrantedAuthority("ROLE_ADMIN"))) {
#       throw new AccessDeniedException("Not authorized to modify this user");
#   }