CVE-2026-75896: Liderahenk Hard-coded Credentials Vulnerability

CVE-2026-75896 Overview

CVE-2026-75896 is a hard-coded credentials vulnerability in TÜBİTAK BİLGEM Software Technologies Research Institute Liderahenk. The flaw allows unauthenticated network attackers to authenticate using common or default usernames and passwords embedded in the product. Liderahenk is an open-source Linux endpoint management platform used to centrally administer client systems. The issue affects all Liderahenk versions before 3.5.5. Because the credentials are static and known, exploitation requires no user interaction and no prior privileges. This weakness maps to [CWE-798] (Use of Hard-coded Credentials).

Critical Impact
Remote attackers can authenticate to Liderahenk with hard-coded credentials, gaining administrative access to managed endpoints and their configuration data.

Affected Products

TÜBİTAK BİLGEM Liderahenk versions prior to 3.5.5

Discovery Timeline

2026-08-26 - CVE-2026-75896 published to NVD
2026-08-26 - Last updated in NVD database

Technical Details for CVE-2026-75896

Vulnerability Analysis

Liderahenk ships with hard-coded authentication credentials that are identical across deployments. An attacker with network reachability to a Liderahenk server can submit these known credentials to authenticate as a privileged user. Because Liderahenk manages Linux clients centrally, authenticated access typically enables policy manipulation, task execution on managed endpoints, and disclosure of configuration data covering entire fleets. The attack requires no social engineering, no exploitation chain, and no local access.

Root Cause

The root cause is the inclusion of static credentials within the Liderahenk distribution, cataloged as [CWE-798]. Credentials embedded in source code, configuration files, or binaries cannot be rotated by operators without vendor intervention. Any party with access to the software, its packages, or public documentation can extract the credential material and reuse it against any deployment that has not upgraded past the fix.

Attack Vector

Exploitation occurs over the network against exposed Liderahenk management interfaces. An attacker submits the hard-coded credentials to the authentication endpoint and receives a valid session. From that session, the attacker can query managed endpoint inventory, push tasks or configuration policies, and read sensitive directory or agent data. No specific exploitation code is required beyond replaying the known credentials against the login flow. See the Siber Güvenlik Notification TR-26-0916 for advisory details.

Detection Methods for CVE-2026-75896

Indicators of Compromise

Successful authentications to Liderahenk from IP addresses outside expected administrator ranges.
Login events using default or built-in account names not associated with provisioned administrators.
Unexpected task pushes, policy changes, or agent command executions initiated from the Liderahenk console.
Outbound connections from Liderahenk-managed endpoints to unfamiliar infrastructure following configuration changes.

Detection Strategies

Audit Liderahenk authentication logs for logins that use built-in or non-provisioned accounts.
Correlate management-console activity with change tickets to surface unauthorized administrative actions.
Alert on new task or policy deployments occurring outside approved maintenance windows.

Monitoring Recommendations

Forward Liderahenk application and authentication logs to a centralized SIEM or data lake for retention and correlation.
Monitor network traffic to the Liderahenk management port from non-administrative network segments.
Track version metadata across Liderahenk servers to confirm all instances are at 3.5.5 or later.

How to Mitigate CVE-2026-75896

Immediate Actions Required

Upgrade all Liderahenk servers to version 3.5.5 or later without delay.
Restrict network access to the Liderahenk management interface to trusted administrative subnets only.
Review authentication logs for prior use of default or built-in accounts and revoke any active sessions.
Rotate credentials, API tokens, and agent enrollment secrets associated with Liderahenk after patching.

Patch Information

Upgrade Liderahenk to version 3.5.5 or later, which remediates the hard-coded credentials condition. Refer to the Siber Güvenlik Notification TR-26-0916 for vendor-coordinated advisory details.

Workarounds

Place the Liderahenk management interface behind a VPN or jump host to prevent direct network exposure.
Enforce firewall access control lists that permit only known administrator source IP addresses.
Disable or block any built-in accounts that cannot be removed until the patch is applied.

bash

# Example: restrict Liderahenk management port to an administrative subnet
iptables -A INPUT -p tcp --dport 8181 -s 10.10.20.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 8181 -j DROP