External risk intelligence

LTSecurity LTK3500SF Hard-coded Credentials Enable Root Access via Telnet SSH

CVE advisorySeverity: CRITICAL (CVSS 9.2)

CVE-2026-47116

The vulnerability involves Telnet and SSH services on an appliance (LTK3500SF). These remote administration protocols are commonly enabled and exposed on network appliances, gateways, or edge devices to facilitate management, making them reachable from the internet in many typical real-world deployment scenarios.

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This advisory details a critical vulnerability in LTSecurity LTK3500SF devices, where hard-coded credentials allow unauthorized root-level access via Telnet and SSH. The primary concern is to confirm if these services are active and exposed, as this could lead to a significant compromise of the device's operating system.

Weak passwords allow full system control.
Critical access vulnerability on network devices.
Assess device exposure and credential security.

Attack Path

How an attacker could exploit the issue

An attacker could gain unauthorized root access to the device by exploiting hard-coded credentials. This involves recovering weak password hashes found on the device, which then allows authentication through the Telnet or SSH services. Exploitation is contingent on these services being active, whether by default configuration or manual enablement.

Entry condition: Network access required.
Trigger point: Weak password hashes recoverable.
Resulting risk: Unauthorized root access.

Live Threat

Current exploitation, exposure, and threat context

The LTSecurity LTK3500SF device has hard-coded credentials for root and guest accounts. If the Telnet or SSH services are running, an attacker could recover these weak credentials and gain root-level access to the operating system. This exploitation is possible when the device's configuration enables Telnet or SSH, or if they are manually started.

System credentials could be compromised.
Weak hashes allow credential recovery.
Root access to the device operating system.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability affects LTSecurity LTK3500SF devices, potentially exposing root-level access. The primary responsibility for addressing this likely falls to infrastructure or device management teams who oversee these appliances. The initial step involves identifying all deployed LTK3500SF units, determining if their Telnet or SSH services are active and externally reachable, and confirming their business criticality before planning remediation.

Infrastructure or device management teams own this.
Verify Telnet/SSH status and reachability.
Plan remediation based on exposure.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

Free EASM Trial See How Signal Works

Frequently asked questions

What is the LTSecurity LTK3500SF?

The LTK3500SF is a network appliance typically deployed as a gateway or edge device. These systems are used to manage network traffic and connectivity. Because they operate at the edge of a network, they often include administrative services like Telnet and SSH to allow remote management by administrators.

What does CWE-798 mean for CVE-2026-47116?

CWE-798 refers to the use of hard-coded credentials. In the case of this CVE, the device stores passwords for the root and guest accounts using weak hashes. Because these are embedded in the system, an attacker can extract these hashes and use automated tools to crack them, ultimately revealing the actual passwords used to log in.

When can an attacker exploit this vulnerability?

An attacker can only exploit this if the Telnet or SSH services are active on the device. If these services are disabled or were never started by a user or configuration, the entry point for authentication does not exist. Simply having the device powered on is not enough; the remote management service must be reachable and running.

Why is this device considered high risk?

According to Halo Surface Signal, this vulnerability is classified as likely because Telnet and SSH are frequently enabled on network appliances to support remote administration. When these devices are deployed in internet-facing configurations, the management services become reachable from outside the network, significantly increasing the probability of unauthorized access.

How should I respond if I manage these devices?

Your first step is to locate all deployed LTK3500SF units within your infrastructure. Once identified, check if Telnet or SSH services are currently enabled or running. If you find these services active, assess whether they are reachable from the network and determine the device's business function to prioritize your next steps for mitigation.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.