CVE-2026-6280: Nomysem Information Disclosure Vulnerability

CVE-2026-6280 Overview

CVE-2026-6280 is an information disclosure vulnerability in NOMYSOFT Informatics Education and Consulting Inc.'s Nomysem product. The flaw stems from incompatible access control policies that allow authenticated users to access functionality not properly constrained by access control lists (ACLs). The issue is classified under [CWE-213] (Exposure of Sensitive Information Due to Incompatible Policies). Affected versions include Nomysem through build 08072026. The vendor was contacted early about this disclosure but did not respond, leaving the vulnerability unpatched at the time of publication.

Critical Impact
An authenticated network attacker with low privileges can access sensitive information exposed by functionality that lacks proper ACL enforcement, resulting in confidentiality loss without user interaction.

Affected Products

NOMYSOFT Nomysem through build 08072026
Earlier Nomysem builds inheriting the same access control logic
Deployments exposing Nomysem functionality over the network

Discovery Timeline

2026-07-08 - CVE-2026-6280 published to the National Vulnerability Database (NVD)
2026-07-08 - Last updated in NVD database
Vendor Notification - NOMYSOFT was contacted early but did not respond

Technical Details for CVE-2026-6280

Vulnerability Analysis

CVE-2026-6280 is an information disclosure vulnerability rooted in incompatible authorization policies within the Nomysem application. Functionality intended to be restricted is reachable by users whose privilege level should not permit access. An authenticated user with low privileges can invoke these endpoints or features over the network and retrieve confidential data.

The vulnerability requires authentication but no user interaction. The scope remains unchanged, and only confidentiality is affected. Integrity and availability of the target system are not directly impacted by exploitation. The Turkish national cybersecurity coordination center published advisory TR-26-0516 documenting the finding.

Root Cause

The root cause is a mismatch between the intended access control policy and its enforcement. Application logic exposes functions or data endpoints without validating that the requesting principal holds the required role or permission. This category of flaw, tracked as [CWE-213], typically arises when access decisions are enforced inconsistently across application layers or when policy definitions in different components disagree.

Attack Vector

An attacker must possess valid low-privilege credentials for the Nomysem instance. Once authenticated, the attacker issues network requests to functionality that should be restricted to higher-privileged roles. Because access control is not applied consistently, the server processes the request and returns sensitive information. No social engineering, phishing, or client-side interaction is required.

No verified proof-of-concept code is publicly available. Refer to the Siber Güvenlik Notification TR-26-0516 for additional technical context.

Detection Methods for CVE-2026-6280

Indicators of Compromise

Repeated authenticated HTTP requests from low-privilege accounts to administrative or restricted Nomysem endpoints
Unusual volumes of successful 200 OK responses to resources typically reserved for elevated roles
Session activity showing lateral access to records or configuration data outside the user's assigned scope

Detection Strategies

Enable verbose application-layer logging on Nomysem to capture the requesting user, endpoint, and response size for every authorized action
Correlate authenticated user roles with accessed resources and alert on mismatches between role and resource sensitivity
Baseline normal per-role access patterns and flag deviations that suggest ACL bypass

Monitoring Recommendations

Forward Nomysem access logs and web server logs to a centralized SIEM for role-aware analytics
Monitor for enumeration behavior such as sequential identifier access or repeated requests to restricted paths
Review authentication events and account provisioning changes to detect newly created low-privilege accounts probing restricted functionality

How to Mitigate CVE-2026-6280

Immediate Actions Required

Restrict network exposure of Nomysem to trusted networks and VPN-authenticated users until a patch is available
Audit user accounts and remove or disable low-privilege accounts that are inactive or unnecessary
Enforce least privilege on Nomysem role assignments and rotate credentials for shared or service accounts
Deploy a reverse proxy or web application firewall in front of Nomysem to filter requests to sensitive endpoints

Patch Information

No vendor patch is available. NOMYSOFT Informatics Education and Consulting Inc. did not respond to disclosure attempts, and no fixed build has been published beyond 08072026. Organizations should track vendor communications and the Siber Güvenlik advisory TR-26-0516 for updates.

Workarounds

Place Nomysem behind network segmentation controls that limit access to authorized administrators
Implement compensating access controls at the reverse proxy layer to block unauthenticated and low-privilege requests to sensitive paths
Increase logging retention and alert thresholds so that any ACL bypass attempts generate immediate investigation
Consider suspending Nomysem functionality that handles sensitive data until the vendor releases a fix

bash

# Example nginx reverse proxy restriction for Nomysem administrative paths
location ~ ^/(admin|config|reports|users)/ {
    allow 10.0.0.0/8;
    deny all;
    proxy_pass http://nomysem_backend;
    proxy_set_header X-Real-IP $remote_addr;
}