CVE-2026-9410: Invoice-System Auth Bypass Vulnerability

CVE-2026-9410 Overview

CVE-2026-9410 is an improper authorization vulnerability in the Sushmi-pal Invoice-System, affecting the Profile Workflow component reached via the /profile endpoint. An authenticated remote attacker can manipulate the ID argument to access or modify profile data belonging to other users. The flaw maps to [CWE-266: Incorrect Privilege Assignment] and is exploitable over the network with low privileges and no user interaction. The project uses rolling releases, so no fixed version is published. The vendor did not respond to the disclosure attempt, and the proof of concept has been published.

Critical Impact

Authenticated attackers can manipulate the ID parameter on /profile to read or alter other users' profile data without authorization.

Affected Products

• Sushmi-pal Invoice-System up to commit a0a3faa16dee2621b231ae227333f5761607283b
• Profile Workflow component (/profile endpoint)
• Rolling-release builds; no discrete version identifiers published

Discovery Timeline

• 2026-05-25 - CVE-2026-9410 published to NVD
• 2026-05-26 - Last updated in NVD database

Technical Details for CVE-2026-9410

Vulnerability Analysis

The vulnerability resides in the Profile Workflow of the Sushmi-pal Invoice-System. The /profile route accepts an ID argument that identifies which profile record to act upon. The application fails to verify that the authenticated session owns the requested ID before serving or modifying the record. As a result, any authenticated user can substitute an arbitrary identifier and operate on another user's profile.

This behavior is a classic Insecure Direct Object Reference pattern realized as improper authorization. The attack succeeds remotely over standard HTTP, requires low privileges, and needs no user interaction. The impact is limited to integrity of profile data, with no observed effect on confidentiality of unrelated assets or service availability. A public proof of concept has been disclosed through a GitHub Gist and VulDB entries.

Root Cause

The application performs authentication but omits an authorization check that binds the supplied ID to the current session principal. Without this ownership check, the access control decision collapses to whichever ID the client supplies, which is the defining condition of [CWE-266] in this implementation.

Attack Vector

An attacker authenticates with any low-privileged account, issues a request to /profile with a target user's identifier in the ID parameter, and the server returns or mutates that user's profile. Because the request is well-formed and uses valid credentials, the activity blends with normal application traffic. Refer to the GitHub Gist PoC Repository and VulDB #365391 for the disclosed request details.

Detection Methods for CVE-2026-9410

Indicators of Compromise

• Requests to /profile where the ID parameter does not match the authenticated session's user identifier.
• A single authenticated session iterating sequential or enumerated values of the ID parameter against /profile.
• Profile modifications immediately followed by login activity from a different source for the affected account.

Detection Strategies

• Add server-side audit logging that records the authenticated user, the supplied ID, and whether the two match on each /profile request.
• Build a SIEM correlation rule that alerts when one session touches more than a threshold of distinct profile IDs in a short window.
• Replay traffic in a staging environment using the public PoC to validate that detections fire on the exact request shape.

Monitoring Recommendations

• Monitor web access logs and application logs for high cardinality of ID values per session against /profile.
• Track unexpected updates to user profile records and reconcile them against the authenticated principal that performed the change.
• Alert on bursts of 4xx/2xx access patterns to /profile that suggest authorization probing or enumeration.

How to Mitigate CVE-2026-9410

Immediate Actions Required

• Enforce a server-side authorization check on /profile that confirms the authenticated session owns the requested ID.
• Reject or ignore client-supplied ID parameters and derive the target profile from the session principal where possible.
• Rotate credentials and review profile records for unauthorized modifications since deployment.

Patch Information

The vendor maintains the project as a rolling release and, per the disclosure, did not respond to outreach. No official patched build identifier is available. Operators should apply a local fix that introduces an ownership check in the /profile handler and pin deployments to a vetted commit ahead of a0a3faa16dee2621b231ae227333f5761607283b. Track the VulDB #365391 entry for any future vendor response.

Workarounds

• Place the application behind a reverse proxy or WAF rule that strips or validates the ID parameter on /profile.
• Restrict the Invoice-System to trusted internal networks until an authorization check is implemented.
• Reduce account privileges and disable self-service registration to limit who can reach the vulnerable endpoint.

# Example nginx rule to block external ID tampering on /profile
location = /profile {
    if ($arg_ID != "") {
        return 403;
    }
    proxy_pass http://invoice_backend;
}