CVE-2026-1768: Devolutions Server Auth Bypass Vulnerability

CVE-2026-1768 Overview

A permission cache poisoning vulnerability has been identified in Devolutions Server that allows authenticated users to bypass permission controls and access entries they should not have access to. This authorization bypass vulnerability (CWE-863) affects the permission caching mechanism, enabling attackers with valid credentials to circumvent the intended access control restrictions.

Critical Impact

Authenticated attackers can bypass permission controls to access sensitive credential entries and secrets stored in Devolutions Server, potentially exposing privileged credentials and confidential information across the organization.

Affected Products

• Devolutions Server versions prior to 2025.3.15

Discovery Timeline

• 2026-02-24 - CVE-2026-1768 published to NVD
• 2026-02-26 - Last updated in NVD database

Technical Details for CVE-2026-1768

Vulnerability Analysis

This vulnerability involves improper authorization (CWE-863) within the permission caching layer of Devolutions Server. The flaw allows authenticated users to manipulate or exploit the permission cache in a way that grants them unauthorized access to entries beyond their assigned privileges.

The attack requires network access and a valid authenticated session with low-privilege credentials. Once authenticated, an attacker can exploit the cache poisoning mechanism to access entries that would normally be restricted based on their role or group membership. This represents a horizontal privilege escalation scenario where users can view entries belonging to other users or groups.

The confidentiality impact is limited to unauthorized read access of entry data, with no direct impact on integrity or availability of the system. However, given that Devolutions Server is used for storing sensitive credentials and secrets, even read-only access to unauthorized entries can lead to significant security breaches.

Root Cause

The root cause lies in the permission caching mechanism within Devolutions Server. The cache does not properly validate or isolate permission states between different user contexts, allowing a poisoned cache entry to be served to users who should not have access to the associated data. This incorrect authorization check enables authenticated users to bypass the intended permission model.

Attack Vector

The attack is network-based and requires the attacker to have valid authentication credentials to Devolutions Server. The attacker leverages the cache poisoning vulnerability to manipulate how permissions are resolved for specific entries.

The exploitation flow involves:

1. Authenticating to Devolutions Server with valid credentials
2. Exploiting the permission cache mechanism to poison cache entries
3. Accessing entries that should be restricted based on the user's actual permissions
4. Retrieving sensitive credential data from unauthorized entries

Technical exploitation details are available in the Devolutions Security Advisory DEVO-2026-0004.

Detection Methods for CVE-2026-1768

Indicators of Compromise

• Unusual access patterns where users retrieve entries outside their normal scope of work
• Permission cache inconsistencies or cache invalidation anomalies in server logs
• Access log entries showing users viewing entries they are not members of
• Repeated authentication followed by rapid entry enumeration attempts

Detection Strategies

• Monitor Devolutions Server audit logs for access to entries by users without explicit permissions
• Implement alerting on unusual entry access patterns that deviate from baseline user behavior
• Review access control configurations and compare against actual access patterns
• Deploy network monitoring to detect anomalous API calls to entry retrieval endpoints

Monitoring Recommendations

• Enable detailed audit logging in Devolutions Server for all entry access operations
• Configure SIEM rules to correlate user permissions with actual access events
• Implement user behavior analytics to detect anomalous access to sensitive entries
• Regularly review access logs for permission boundary violations

How to Mitigate CVE-2026-1768

Immediate Actions Required

• Upgrade Devolutions Server to version 2025.3.15 or later immediately
• Review access logs for any unauthorized entry access that may indicate exploitation
• Audit current user permissions and entry access controls
• Consider temporarily restricting access to sensitive entries until patching is complete

Patch Information

Devolutions has released version 2025.3.15 to address this vulnerability. Organizations should upgrade to this version or later as soon as possible. For detailed patch information and upgrade instructions, refer to the Devolutions Security Advisory DEVO-2026-0004.

Workarounds

• Implement network segmentation to limit access to Devolutions Server from trusted networks only
• Enable additional logging and monitoring to detect potential exploitation attempts
• Review and restrict user permissions to the minimum necessary for their roles
• Consider implementing additional authentication controls such as multi-factor authentication

# Review Devolutions Server version
# Ensure version is 2025.3.15 or later
# Check current version in Administration > System Settings > About

# Enable enhanced audit logging
# Navigate to Administration > System Settings > Security
# Enable "Log all entry access" option
# Configure log retention for forensic analysis