CVE-2026-44585: Paymenter Auth Bypass Vulnerability

CVE-2026-44585 Overview

CVE-2026-44585 is an Insecure Direct Object Reference (IDOR) vulnerability in Paymenter, a free and open-source webshop solution for hosting service management. The flaw exists in the ticket creation endpoint in versions prior to 1.5.0. The endpoint accepts a user-supplied service identifier without enforcing ownership validation. Authenticated users can modify the service ID in the client-side request and create support tickets referencing services owned by other accounts. The issue is tracked under [CWE-639: Authorization Bypass Through User-Controlled Key].

Critical Impact
Authenticated attackers can create support tickets referencing services owned by other users, potentially exposing referenced service information to support staff and causing operational confusion.

Affected Products

Paymenter versions prior to 1.5.0
Self-hosted Paymenter deployments used for hosting service management
Paymenter customer ticketing subsystem

Discovery Timeline

2026-07-20 - CVE-2026-44585 published to NVD
2026-07-23 - Last updated in NVD database

Technical Details for CVE-2026-44585

Vulnerability Analysis

The vulnerability resides in the Paymenter ticket creation workflow. When an authenticated user submits a new support ticket, the request includes a service_id parameter identifying the associated hosting service. The endpoint uses this parameter directly to link the ticket to the referenced service. The server does not verify that the authenticated user owns the specified service before persisting the ticket. An attacker with a valid account can substitute another user's service identifier and the backend accepts the request. The resulting ticket becomes associated with a service the attacker does not own.

Exploitation does not return the target service's contents through the vulnerable endpoint. It does not permit modification of the target service or retrieval of confidential customer data directly. However, service metadata referenced in the ticket becomes visible to support personnel who process the ticket. This can enable indirect information exposure through the support workflow and abuse of staff attention.

Root Cause

The root cause is missing ownership validation on the service_id parameter accepted by the ticket creation endpoint. The application trusts a client-supplied object reference without checking whether the authenticated principal is authorized to act on that reference. This pattern matches the classic IDOR anti-pattern described in [CWE-639].

Attack Vector

The attack requires network access and valid authenticated credentials in the Paymenter instance. An attacker intercepts the ticket creation request using a proxy or browser developer tools. The attacker replaces the service_id value with an identifier belonging to another customer. The server processes the request without an ownership check and creates the ticket linked to the target service. No user interaction from the victim is required.

The vulnerability manifests in the ticket creation controller of Paymenter versions prior to 1.5.0. See the GitHub Security Advisory GHSA-x93q-x9pc-w5hw for the maintainer's technical description and fix reference.

Detection Methods for CVE-2026-44585

Indicators of Compromise

Support tickets created by user accounts that reference service_id values not owned by the submitting user in the Paymenter database.
Unexpected spikes in ticket creation volume from a single authenticated account.
Support staff reports of tickets referencing services that do not match the submitting customer's account context.

Detection Strategies

Query the Paymenter database to correlate tickets.user_id with services.user_id for the referenced service_id and flag mismatches.
Enable verbose request logging on the ticket creation endpoint and inspect payloads for service_id values that do not belong to the authenticated session user.
Review web application firewall logs for repeated POST requests to the ticket creation route with varying service_id values from the same source.

Monitoring Recommendations

Monitor Paymenter application logs for authorization decisions or the absence of them around ticket creation.
Alert on tickets created within short time windows that reference services across multiple distinct owners.
Track support agent reports of anomalous ticket associations as a human-in-the-loop detection signal.

How to Mitigate CVE-2026-44585

Immediate Actions Required

Upgrade Paymenter to version 1.5.0 or later, which contains the ownership validation fix.
Audit existing tickets for cross-account service_id references and remediate any that appear illegitimate.
Communicate remediation guidance to support staff so they verify the customer-to-service relationship before acting on ticket contents.

Patch Information

The maintainers fixed the issue in Paymenter 1.5.0. The fix enforces ownership validation on the service_id parameter submitted to the ticket creation endpoint. Details are documented in the Paymenter GitHub Security Advisory GHSA-x93q-x9pc-w5hw.

Workarounds

If upgrading is not immediately possible, restrict access to the Paymenter panel to trusted users while remediation is scheduled.
Add a reverse-proxy or web application firewall rule that inspects ticket creation requests and rejects payloads where the service_id does not correspond to the authenticated session.
Implement manual verification in the support workflow requiring agents to confirm the referenced service belongs to the ticket submitter.

bash

# Upgrade Paymenter to the patched release
cd /var/www/paymenter
git fetch --tags
git checkout v1.5.0
composer install --no-dev --optimize-autoloader
php artisan migrate --force
php artisan config:cache