Executive Intelligence Brief

A critical vulnerability has been identified in UTT HiPER 1250GW devices up to version 3.2.7-210907-180535. This vulnerability, tracked as CVE-2026-76004, is a stack-based buffer overflow in the HTTP Handler component. It has a CVSS score of 9.9, indicating high severity. The vulnerability can be exploited remotely and has been publicly disclosed, although it is not currently being actively exploited. Organizations using affected versions should immediately apply patches or mitigations to prevent potential attacks.

Threat Overview

The UTT HiPER 1250GW is a networking device used for various connectivity and management purposes. The vulnerability affects the device's HTTP Handler component, specifically the /goform/aspApBasicConfigUrcp file. The strcpy function is vulnerable to a stack-based buffer overflow when the pvid argument is manipulated. This type of vulnerability can lead to remote code execution (RCE), allowing an attacker to gain control over the device.

Historically, vulnerabilities in networking devices like the HiPER 1250GW have been attractive targets for threat actors due to their potential for widespread impact and the difficulty in securing them.

Technical Deep Dive

Vulnerability Classification

CVE-2026-76004 is classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) and CWE-121 (Stack-based Buffer Overflow). A stack-based buffer overflow occurs when more data is written to a buffer than it can hold, causing the extra data to spill over into adjacent areas of the stack. This can lead to arbitrary code execution, as the return address on the stack can be overwritten.

The CVSS vector for this vulnerability is CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H, indicating a high severity score of 9.9. The vector breaks down as follows:

  • AV:N: Attack Vector - Network
  • AC:L: Attack Complexity - Low
  • PR:L: Privileges Required - Low
  • UI:N: User Interaction - None
  • S:C: Scope - Changed
  • C:H: Confidentiality Impact - High
  • I:H: Integrity Impact - High
  • A:H: Availability Impact - High

Root Cause Analysis

The root cause of this vulnerability is the improper handling of input in the strcpy function within the /goform/aspApBasicConfigUrcp file. Specifically, the pvid argument is not properly validated or sanitized, allowing an attacker to provide a crafted input that overflows the buffer.

Attack Vector & Chain

The attack vector for CVE-2026-76004 involves exploiting the stack-based buffer overflow in the HTTP Handler component. An attacker can send a specially crafted request to the /goform/aspApBasicConfigUrcp endpoint, manipulating the pvid argument to trigger the buffer overflow. This can lead to remote code execution.

Exploitation Scenario Walkthrough

Scenario: Remote Code Execution via Stack-Based Buffer Overflow

Reconnaissance: An attacker discovers a UTT HiPER 1250GW device with a vulnerable version (up to 3.2.7-210907-180535) through network scanning or device inventory.

Weaponization: The attacker crafts a malicious request to the /goform/aspApBasicConfigUrcp endpoint, including a specially designed pvid argument that overflows the buffer.

Delivery & Exploitation: The attacker sends the crafted request to the device. The HTTP Handler processes the request, and the buffer overflow is triggered, allowing the attacker to execute arbitrary code.

Post-Exploitation: The attacker gains control over the device, potentially leading to further exploitation, such as configuration changes, data exfiltration, or lateral movement within the network.

Impact Realization: The attacker achieves remote code execution, potentially leading to a full compromise of the device and impacting network integrity and confidentiality.

Exploitation in the Wild

While CVE-2026-76004 has not been actively exploited at the time of disclosure, the exploit has been publicly disclosed. This increases the likelihood of future exploitation attempts. Threat actors may target vulnerable devices for various malicious activities, including botnet recruitment, data theft, or further network penetration.

Impact Analysis

Direct Impact

The direct impact of CVE-2026-76004 is remote code execution, which can lead to:

  • Full device compromise
  • Configuration changes
  • Data exfiltration
  • Lateral movement within the network

Downstream & Cascading Effects

The downstream effects may include:

  • Supply chain risk: Compromised devices can be used to attack other parts of the network or supply chain.
  • Regulatory implications: Breaches resulting from exploitation may lead to regulatory actions.
  • Customer data exposure: Sensitive data may be accessed or leaked.
  • Operational disruption: Network operations may be significantly disrupted.

Affected Products & Versions

The following products and versions are affected:

  • UTT HiPER 1250GW up to version 3.2.7-210907-180535

Detection & Threat Hunting

Indicators of Compromise

Indicators of compromise (IoCs) may include:

  • Unusual traffic to or from the device
  • Logs indicating access to the /goform/aspApBasicConfigUrcp endpoint with suspicious parameters
  • Anomalies in device behavior or configuration changes

Detection Rules & Signatures

Detection logic may involve:

  • Monitoring HTTP traffic to the device, especially requests to the /goform/aspApBasicConfigUrcp endpoint
  • Implementing WAF rules to detect and block suspicious pvid arguments
  • Logging and analyzing device configuration changes

Threat Hunting Queries

Threat hunting queries may include:

  • Searching logs for unusual access to the /goform/aspApBasicConfigUrcp endpoint
  • Identifying devices with version 3.2.7-210907-180535 or earlier
  • Analyzing network traffic for anomalies related to the device

Remediation & Hardening

Immediate Actions (0-24 hours)

Organizations should:

  • Apply the available patch or update to version 3.2.7-210907-180536 or later
  • Implement temporary mitigations such as restricting access to the /goform/aspApBasicConfigUrcp endpoint

Short-Term Hardening (1-7 days)

Additional security controls:

  • Network segmentation to limit device access
  • WAF rules to detect and block suspicious traffic
  • Enhanced monitoring of device logs and traffic

Strategic Recommendations

Long-term recommendations:

  • Regularly update and patch devices
  • Implement robust network security controls
  • Conduct regular vulnerability assessments and penetration testing

Analyst Assessment

The risk of CVE-2026-76004 is high due to its critical severity, public disclosure of the exploit, and potential for remote code execution. Organizations should prioritize patching or mitigating this vulnerability to prevent potential attacks. The likelihood of exploitation is expected to increase over time as threat actors become more aware of the vulnerability.

Sources