CVE-2026-24776: OpenProject Privilege Escalation Flaw

CVE-2026-24776 Overview

CVE-2026-24776 is an Insecure Direct Object Reference (IDOR) vulnerability affecting OpenProject, an open-source, web-based project management software. The vulnerability exists in the drag-and-drop handler used for moving agenda items between meeting sections. Prior to version 17.0.2, the handler failed to properly verify whether the target meeting section belongs to the same meeting or is a valid backlog section for recurring meetings. This oversight allows an authenticated attacker to move meeting agenda items into different meetings, potentially causing confusion and enabling unauthorized modification of meeting content.

Critical Impact

Authenticated attackers can inject arbitrary agenda items into meetings they do not have access to, compromising the integrity of meeting content and potentially disrupting organizational workflows.

Affected Products

• OpenProject versions prior to 17.0.2

Discovery Timeline

• February 6, 2026 - CVE CVE-2026-24776 published to NVD
• February 6, 2026 - Last updated in NVD database

Technical Details for CVE-2026-24776

Vulnerability Analysis

This vulnerability is classified as CWE-639: Authorization Bypass Through User-Controlled Key. The flaw resides in the meeting agenda item management functionality of OpenProject. When users drag and drop agenda items to reorganize meeting sections, the application performs insufficient validation on the target destination.

The core issue is that the server-side handler accepts a target meeting section identifier without validating its relationship to the source meeting. An authenticated user can manipulate the target section parameter to reference a section belonging to a completely different meeting, effectively injecting agenda items into meetings they should not be able to modify.

While this vulnerability does not grant the attacker read access to other meetings or their content, it does allow them to add agenda items that appear legitimate to meeting participants. This can lead to social engineering attacks, disruption of meeting workflows, or insertion of misleading information into organizational records.

Root Cause

The root cause is insufficient authorization validation in the drag-and-drop handler for meeting agenda items. The handler accepts user-controlled input (the target section ID) without verifying that the target section belongs to the same meeting as the source agenda item. This is a classic example of broken object-level authorization where the application trusts client-supplied identifiers without proper backend validation.

Attack Vector

The attack requires network access and low-privilege authentication to OpenProject. An attacker with a valid user account can exploit this vulnerability through the following mechanism:

1. The attacker authenticates to OpenProject with valid credentials
2. The attacker accesses a meeting where they have permission to view or edit agenda items
3. Using the drag-and-drop functionality (or by directly manipulating the API request), the attacker modifies the target section ID to point to a section in a different meeting
4. The server processes the request without validating meeting ownership, moving the agenda item to the unauthorized meeting

The attack can be performed by intercepting and modifying the HTTP request that handles agenda item movement, changing the target section identifier to reference a meeting section the attacker should not have write access to. For detailed technical information, refer to the GitHub Security Advisory GHSA-p9v8-w9ph-hqmf.

Detection Methods for CVE-2026-24776

Indicators of Compromise

• Unexpected or unfamiliar agenda items appearing in meeting records
• Meeting agenda modifications from users who should not have access to specific meetings
• Unusual API request patterns involving meeting section movements with mismatched meeting identifiers
• Audit log entries showing agenda item transfers between unrelated meetings

Detection Strategies

• Monitor application logs for agenda item movement operations where source and target meeting IDs differ
• Implement alerting for high volumes of meeting modification requests from single user accounts
• Review audit trails for cross-meeting agenda item transfers that violate expected access boundaries
• Deploy web application firewall rules to detect parameter manipulation in meeting-related API endpoints

Monitoring Recommendations

• Enable detailed audit logging for all meeting agenda modification operations
• Configure alerts for meeting modifications by users without explicit meeting membership
• Regularly review meeting content integrity as part of routine security audits
• Monitor for unusual patterns in the meeting management API endpoints

How to Mitigate CVE-2026-24776

Immediate Actions Required

• Upgrade OpenProject to version 17.0.2 or later immediately
• Review meeting audit logs for any suspicious agenda item modifications prior to patching
• Verify the integrity of critical meeting records that may have been modified
• Notify users to report any unexpected agenda items discovered in their meetings

Patch Information

OpenProject has released version 17.0.2 to address this vulnerability. The fix implements proper validation to ensure that target meeting sections belong to the same meeting as the source agenda item before allowing the move operation. Organizations should upgrade to this version or later as soon as possible.

For additional details, see the GitHub Release v17.0.2 and the GitHub Security Advisory GHSA-p9v8-w9ph-hqmf.

Workarounds

• Temporarily restrict meeting agenda editing permissions to trusted administrators only
• Disable the drag-and-drop functionality for meeting agenda items if technically feasible
• Implement additional network-level access controls to limit exposure of the OpenProject instance
• Consider placing OpenProject behind a VPN or additional authentication layer until patching is complete

# Upgrade OpenProject to patched version
# For packaged installations, update to version 17.0.2 or later
# Consult OpenProject documentation for your specific deployment method

# Example for Docker-based deployments:
docker pull openproject/community:17.0.2
docker-compose down
docker-compose up -d