External risk intelligence

GX Group GPON ONT Privilege Escalation via Login Brute Force.

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2022-40055

The affected product is a GPON ONT (Optical Network Terminal), which is an edge networking device used by service providers to deliver internet connectivity. Such devices are designed to be at the network edge and often have management interfaces that are directly exposed or easily accessible from the internet in standard residential and small office deployment patterns.

Gxgroup Gpon Ont Titanium 2122a Firmware

t2122-v1.26exl

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

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This advisory addresses a critical vulnerability in GX Group GPON ONT Titanium devices, specifically impacting the T2122-V1.26EXL firmware. The flaw could allow unauthorized access and control by enabling privilege escalation through brute-force attacks on the login page. Such devices are crucial for network connectivity, making their compromise a significant concern for service providers and their customers.

Login weakness allows unauthorized access and control.
Concerns critical network edge devices used by internet providers.
Focus on confirming relevance and potential exposure.

Attack Path

How an attacker could exploit the issue

An attacker can reach the vulnerable component over the network. The login page of the GX Group GPON ONT Titanium 2122A is exposed, allowing unauthenticated attackers to attempt to gain administrative access through repeated login attempts. Successful brute-forcing could lead to privilege escalation, granting the attacker high levels of control over the device.

Requires network access to the device.
Brute force attempts on the login page.
Privilege escalation to gain device control.

Live Threat

Current exploitation, exposure, and threat context

A brute force attack against the login page of the GX Group GPON ONT Titanium 2122A could allow an unauthenticated attacker to escalate privileges. This means an attacker could gain administrative control over the device.

Device management access.
Brute force login attempts.
Unauthorized system control.

Operational Fix

Recommended remediation, mitigation, and detection steps

The identified privilege escalation vulnerability in GX Group GPON ONT Titanium 2122A firmware requires immediate attention from the teams responsible for network edge devices and their security. Initial steps should focus on identifying all instances of this firmware, determining their exposure to the internet, assessing business criticality, and locating the accountable asset owners before planning any remediation.

Network and security teams own this issue.
Verify external reachability and business impact.
Coordinate vendor engagement and plan remediation.

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.

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Frequently asked questions

What is the GX Group GPON ONT Titanium 2122A?

This device is an Optical Network Terminal, a fundamental piece of hardware provided by internet service providers. It acts as the gateway at the network edge, converting optical fiber signals into the wired or wireless internet connectivity used in residential and small office settings to connect devices to a wide-area network.

How does CVE-2022-40055 enable privilege escalation?

This vulnerability is categorized as CWE-307, which refers to improper restriction of excessive authentication attempts. Because the device does not sufficiently limit login tries, an attacker can perform a brute-force attack on the management page. By cycling through many password combinations, they can bypass standard security to gain administrative control over the unit.

Do I need to be authenticated to trigger CVE-2022-40055?

No. The flaw exists on the device's login page, meaning an attacker does not need prior access or legitimate credentials to initiate the attack. The vulnerability is triggered solely by the act of submitting numerous login attempts remotely. It is not triggered by normal administrative operations or internal traffic that does not target the login interface.

Is my device at risk based on Halo Surface Signal?

Halo Surface Signal indicates that this device is a 'very likely' target. Because these terminals are designed to sit at the network edge to provide internet access, their management interfaces are often placed where they are directly reachable from the internet, making them accessible to remote attackers without needing a foothold inside your local network.

What should I do if I am running this firmware?

Begin by auditing your infrastructure to locate all instances of the Titanium 2122A running the affected firmware version. Prioritize identifying which units are exposed to the public internet versus those on private segments. Once identified, coordinate with the appropriate network teams to assess the device's business impact and prepare for vendor-supplied security updates to close the authentication gap.

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.